RESUMO
In order to evaluate the freeze-thaw stability of mung bean protein isolate (MPI)-stabilized emulsions and its relationship with protein structure, proteins of eight mung bean varieties were compared. The results revealed that MPIs prepared from all eight varieties were mainly composed of five subunit bands, with albumin and globulin content ranges of 188.4-310.3 and 301.1-492.7 mg/g total protein, respectively. Protein structural analysis revealed that random coil structure (32.34-33.51%) accounted for greater than 30% of MPI secondary structure. Meanwhile, analysis of protein properties revealed emulsifying activity index (EAI), emulsifying stability index (ESI) and flexibility value ranges of 6.735-8.598 m2/g, 20.13-34.25% and 0.125-0.182, respectively. Measurements of freeze-thaw stability of MPI emulsions demonstrated that exposures of emulsions to multiple freeze-thaw cycles resulted in significantly different emulsion creaming index, oiling-off, particle size and zeta potential values for the various emulsions. Moreover, the stabilities of all eight protein emulsions decreased with each freeze-thaw cycle, as demonstrated using optical micrographs. The correlation analysis method was used to study the correlation between the original structures, emulsifying properties of proteins and the freeze-thaw stability of MPI emulsions. Correlation analysis results revealed significant relationships between albumin content, subunit bands with a molecular weight of 26.9 kDa and emulsifying properties were significantly related to the freeze-thaw stability of MPI emulsion. Thus, by determining these indicator values, we can predict the freeze-thaw stability of MPI-stabilized emulsions.
RESUMO
In order to determine the mechanisms underlying resistant starch formation, three treatments were used to prepare resistant starch from purple sweet potato. The resistant starch yield, amylose content, chain length distribution, thermal properties, and crystal structure were determined, and the results were compared with those of unmodified starch. Autoclaving, pullulanase, and pullulanase-autoclaving treatments significantly increased the resistant starch yield, amylose content, shorter amylopectin branch content, and gelatinisation temperatures of native purple sweet potato starch. Resistant starch prepared via pullulanase-autoclaving combination treatment exhibited the highest gelatinisation enthalpy value and the greatest degree of overall thermal stability. X-ray diffraction patterns and Fourier-transform infrared spectra analysis demonstrated that all three treatments transformed the starch crystalline structure from C-type to B-type, and no new groups were generated during the modification process; all the processes were only physical modifications.
Assuntos
Ipomoea batatas , Amilopectina , Amilose , Amido Resistente , Amido , Difração de Raios XRESUMO
BACKGROUND: After cold storage (CS) and subsequent transplantation, fatty liver is more inclined to develop liver dysfunction and serious postoperative complications in contrast to healthy liver. Hypothermic oxygenated perfusion (HOPE) is a safe and efficacious system, which can repair fatty liver and reduce ischemia-reperfusion injury. The aim of this research is to investigate the function of Brg1/Nrf2/HO-1 signaling pathway in the protective effect of HOPE on ischemia-reperfusion injury of fatty liver. METHODS: The mouse fatty liver model was successfully established and verified by hematoxylin-eosin (HE) staining and oil red O staining. The animals were divided into Control group, CS group and HOPE group. The levels of liver enzyme and lactate in the perfusate were used to measure liver function and cellular metabolism. HE staining and TUNEL staining were utilized to assess the tissue structure and apoptosis, respectively. The levels of superoxide dismutase, malondialdehyde and reactive oxygen species in liver tissue were measured to quantitatively analyze the degree of oxidative stress, and the expressions of protein Brg1, Nrf2 and HO-1 were detected by means of the western blot. Double-labeling immunofluorescence was to explore the colocalization of Brg1 and Nrf2. RESULTS: The injury of the liver in the CS group was more serious than that in the control group. However, HOPE could significantly reduce the injury, which was manifested by the improvement of liver function and cellular metabolism, and the lower degrees of apoptosis, necrosis and oxidative stress. Furthermore, the expressions of Brg1, Nrf2 and HO-1 in the HOPE group were significantly increased than those in the CS group. CONCLUSIONS: One-hour HOPE treatment before reperfusion can obviously improve the injury of fatty liver in mice. The underlying mechanism may be that the interaction of Brg1 and Nrf2 can selectively activate the transcription of HO-1.
Assuntos
Fígado Gorduroso/terapia , Transplante de Fígado , Perfusão/métodos , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose , DNA Helicases/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fígado Gorduroso/patologia , Heme Oxigenase-1/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/metabolismo , Estresse Oxidativo , Transdução de Sinais , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: Donor-derived cell-free DNA (dd-cfDNA) is a potential noninvasive molecular marker of graft rejection after kidney transplant, whose diagnostic accuracy remains controversial. METHODS: We performed a systematic review and metaanalysis to evaluate the diagnostic accuracy of dd-cfDNA. Relevant literature was searched from online databases, and the data on the diagnostic accuracy of discriminating main rejection episodes (MRE) and antibody-mediated rejection (AMR) were merged, respectively. RESULTS: Nine studies were included in the metaanalysis, of which 6 were focused on the diagnostic accuracy of dd-cfDNA for MRE, whose pooled sensitivity, specificity, area under the receiver operating characteristics curve, diagnostic odds ratio, overall positive likelihood ratio, and negative likelihood ratio with 95% confidence intervals were 0.70 (0.57-0.81), 0.78 (0.70-0.84), 0.81 (0.77-0.84), 8.18 (5.11-13.09), 3.15 (2.47-4.02), and 0.39 (0.27-0.55), respectively. Five tests were focused on discriminating AMR, whose pooled indicators were 0.84 (0.75-0.90), 0.80 (0.74-0.84), 0.89 (0.86-0.91), 20.48 (10.76-38.99), 4.13(3.21-5.33), and 0.20(0.12-0.33), respectively. CONCLUSIONS: Donor-derived cell-free DNA can be a helpful marker for the diagnosis of AMR among those recipients suspected of renal dysfunction. Its diagnostic accuracy on the MRE remains uncertain, which requires further prospective, large-scale, multicenter, and common population research.
Assuntos
Ácidos Nucleicos Livres/sangue , Rejeição de Enxerto/diagnóstico , Transplante de Rim/efeitos adversos , Doadores de Tecidos , Biomarcadores/sangue , Rejeição de Enxerto/sangue , Rejeição de Enxerto/genética , Humanos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Resultado do TratamentoRESUMO
Iliac atherosclerosis is common in renal transplant recipients. In severe cases, it affects intraoperative renal arterial anastomosis and increases the risk of postanastomosis complications. At present, safe and efficient vascular replacement methods are relatively limited. In the 2 renal transplant cases at our center, described here, the donors' iliac arteries were unavailable. We therefore attempted to replace the recipients' diseased external iliac artery with the donors' inferior vena cava and then performed an end-to-side grafting with the attachment in arterial reconstruction. One patient received a single kidney transplantation, while the other received a dual kidney transplantation. Antiplatelet/anticoagulation drug application was avoided, and both patients were observed for more than 6 months. Stable renal graft function was achieved without any vascular complications. During this study, all procedures were in compliance with the Helsinki Congress and the Declaration of Istanbul. For end-stage renal disease patients with severe iliac atherosclerosis who are waiting for kidney transplantation, a donor's vena cava graft could potentially be a promising replacement option to restore external iliac artery patency and reconstruct renal blood flow, without the necessity of harvesting a recipient's autologous vessels or looking for costly artificial ones.
Assuntos
Aterosclerose/cirurgia , Artéria Ilíaca/cirurgia , Transplante de Rim/métodos , Enxerto Vascular/métodos , Veia Cava Inferior/transplante , Aterosclerose/etiologia , Humanos , Artéria Ilíaca/patologia , Rim/irrigação sanguínea , Falência Renal Crônica/complicações , Falência Renal Crônica/cirurgia , Masculino , Pessoa de Meia-IdadeRESUMO
ABSTRACT: The inhibition kinetics of glutathione (GSH) and quercetin on acrylamide (AA) formation in the low-moisture Maillard systems were investigated at 180°C. The inhibition rates in an equal-molar asparagine-glucose (Asn-Glc) system were higher than those in an asparagine-fructose (Asn-Fru) system, and the maximum inhibition rates for AA were 57.75% with 10-2 mol L-1 GSH and 51.38% with 10-1 mol L-1 quercetin. The Logistic-Index dynamic model and two consecutive simplified first-order kinetic models were well fitted to the changes of AA in the Asn-Glc system. The kinetics results suggested that the predominant inhibition effect of GSH on AA could be attributed to the competitive reaction between GSH and Asn for the consumption of Glc. The kinetic results and high-pressure liquid chromatography-tandem mass spectrometry analysis of the inhibitory effect of quercetin on AA indicated that quercetin might mitigate AA through the binding reaction of quercetin decomposition products and Maillard intermediate products. These experimental results provide theoretical data that may be useful to control the formation of AA during food thermal processing.
Assuntos
Acrilamida , Quercetina , Asparagina , Glucose , Glutationa , Temperatura Alta , Cinética , Reação de Maillard , Quercetina/farmacologiaRESUMO
Coronavirus disease 2019 (COVID-19) is a novel and lethal infectious disease, posing a threat to global health security. The number of cases has increased rapidly, but no data concerning kidney transplant (KTx) recipients infected with COVID-19 are available. To present the epidemiological, clinical, and therapeutic characteristics of KTx recipients infected with COVID-19, we report on a case series of five patients who were confirmed as having COVID-19 through nucleic acid testing (NAT) from January 1, 2020 to February 28, 2020. The most common symptoms on admission to hospital were fever (five patients, 100%), cough (five patients, 100%), myalgia or fatigue (three patients, 60%), and sputum production (three patients, 60%); serum creatinine or urea nitrogen levels were slightly higher than those before symptom onset. Four patients received a reduced dose of maintenance immunosuppressive therapy during hospitalization. As of March 4, 2020 NAT was negative for COVID-19 in three patients twice in succession, and their computed tomography scans showed improved images. Although greater patient numbers and long-term follow-up data are needed, our series demonstrates that mild COVID-19 infection in KTx recipients can be managed using symptomatic support therapy combined with adjusted maintenance immunosuppressive therapy.
Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Imunossupressores/efeitos adversos , Transplante de Rim/efeitos adversos , Infecções Oportunistas/diagnóstico , Pneumonia Viral/diagnóstico , Transplantados , Adulto , Betacoronavirus/genética , Betacoronavirus/imunologia , COVID-19 , Teste para COVID-19 , China , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Feminino , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/terapia , Infecções Oportunistas/virologia , Pandemias , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Valor Preditivo dos Testes , SARS-CoV-2 , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do TratamentoRESUMO
Inflammation and oxidative stress are pivotal mechanisms for the pathogenesis of ischemia and reperfusion injury (IRI). Vagus nerve stimulation (VNS) may participate in maintaining oxidative homeostasis and response to external stimulus or injury. We investigated whether the in vivo VNS can protect the liver from IRI. In this study, hepatic IRI were induced by ligating the vessels supplying the left and middle lobes of the liver, which underwent 1 h occlusion followed with 24 h reperfusion. VNS was initiated 15 min after ischemia and continued 30 min. Hepatic function, histology, and apoptosis rates were evaluated after 24 h reperfusion. Compared with the IRI group, VNS significantly improved hepatic function. The protective effect was accompanied by a reduction in histological damage in the ischemic area, and the apoptosis rate of hepatocytes has considerable reduction. To find the underlying mechanism, proteomic analysis was performed and differential expression of glutathione synthetase (GSS) and glutathione S-transferase (GST) was observed. Subsequently, test results indicated that VNS upregulated the expression of mRNA and protein of GSS and GST. Meanwhile, VNS increased the plasma levels of glutathione and glutathione peroxidases. We found that VNS alleviated hepatic IRI by upregulating the antioxidant glutathione via the GSS/glutathione/GST signaling pathway.
Assuntos
Glutationa/sangue , Hepatócitos/metabolismo , Hepatopatias/terapia , Traumatismo por Reperfusão/terapia , Estimulação do Nervo Vago , Animais , Antioxidantes/metabolismo , Apoptose/genética , Citocinas/metabolismo , Glutationa/biossíntese , Glutationa/metabolismo , Glutationa Peroxidase/sangue , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Hepatócitos/enzimologia , Fígado/enzimologia , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Hepatopatias/enzimologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Estresse Oxidativo , Proteômica , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Transdução de Sinais/genéticaRESUMO
ABSTRACT: Oil oxidation in an oil-rich system was used to investigate the effect on acrylamide formation. Three kinds of common oil, soybean oil, olive oil, and palm oil, were preheated at different temperatures (120, 150, 180, and 210°C) for different times (0, 5, 10, 15, and 20 h). The oil-rich model systems were composed of pretreated oil and asparagine. Acid value, peroxide value, p-anisidine value, and carbonyl group value were used to monitor the degree of lipid oxidation in the model system. Our results showed that the content of acrylamide increased with oil preheat time and temperature. The highest yield of acrylamide in soybean oil was 0.26 ± 0.012 µg/mL after 20 h of incubation at 210°C. Oil oxidation indices correlated significantly with the content of acrylamide. The peroxide value could provide more information for references about acrylamide formation in soybean and olive oil systems.
RESUMO
Shikonin is a natural naphthoquinone component with antioxidant and anti-tumor function and has been used for hepatocellular carcinoma (HCC) treatment. According to the previous study, many herbs can regulate cancer cell progression by targeting specific microRNA (miRNA) (Liu, 2016). However, the underlying pathological mechanism of shikonin in HCC therapy is still unclear. The detection of cell growth and death rate were performed by hemacytometry and trypan blue staining, respectively. The expression of miR-106b and SMAD7 messenger RNA (mRNA) in HCC cells was evaluated by quantitative real-time polymerase chain reaction. Cell proliferation, apoptosis, and migration ability were measured by cell counting kit-8 (CCK-8), flow cytometry, and transwell assay. The expression of proteins E-cadherin, N-cadherin, vimentin, SMAD7, TGF-ß1, p-SMAD3, SMAD3, and GAPDH was examined by western blot. The interaction between SMAD7 and miR-106b was assessed by luciferase reporter system. Shikonin inhibited Huh7 and HepG2 cell growth in a dose-dependent manner while induced cell death in a time-dependent manner. In addition, the expression of miR-106b was reduced after shikonin treatment. Moreover, miR-106b attenuated the suppressive effects of shikonin on HCC cell migration and epithelial-mesenchymal transition (EMT). SMAD7 was predicted as a target of miR-106b and the prediction was confirmed by luciferase reporter system. Additionally, we observed that SMAD7 reversed the promotive effects of miR-106b on HCC cell progression and EMT. The subsequent western blot assay revealed that shikonin could modulate SMAD7/TGF-ß signaling pathway by targeting miR-106b. In conclusion, Shikonin suppresses cell progression and EMT and accelerates cell death of HCC cells via modulating miR-106b/SMAD7/TGF-ß signaling pathway, suggesting shikonin could be an effective agent for HCC treatment.
Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/genética , Naftoquinonas/farmacologia , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteína Smad7/genética , Fator de Crescimento Transformador beta1/genética , Células Tumorais CultivadasRESUMO
Hypothermic oxygenated machine perfusion (HOPE) is a safe and reliable method that could alleviate liver injury in donation after circulatory death (DCD). This study focuses on the role of autophagy in HOPE's protective effect on DCD liver injury. A 30-minute warm ischemic liver model was established in mice. After 4 hours of cold storage (CS), 1 hour of hypothermic machine perfusion (HMP) with 100% O2 or 100% N2 was employed. During 2 hours of reperfusion, liver tissue and perfusate were collected to evaluate liver function, oxidative stress level, apoptosis, and necrosis. Western blotting was used to explore the level of autophagy. When the liver experienced warm ischemic injury, LC3B-II expression was significantly enhanced. Compared with the CS, HOPE induced lower release of AST and ALT, as well as lower oxidative stress levels, apoptosis, and necrosis cell numbers, and led to higher tissue ATP content. Meanwhile, expression of autophagy-related proteins, such as ULK1, Atg5, and LC3B-II, increased. When oxygen was completely replaced by nitrogen, the washout effect of HMP did not activate autophagy and did not relieve DCD liver injury. When the autophagy inhibitor 3-methyladenine was used in HOPE, the protective effect of HOPE was attenuated. In conclusion, DCD liver injury activated autophagy compared with healthy liver, while HOPE alleviated DCD liver injury by increasing autophagy levels further in this mouse model. However, HMP with 100% of N2 had no beneficial effect on DCD liver injury or on autophagy levels compared with CS. The research on autophagy may provide a new strategy for alleviating DCD liver injury in clinical practice.
Assuntos
Autofagia , Fígado/fisiologia , Preservação de Órgãos/métodos , Oxigênio/metabolismo , Perfusão/métodos , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Autofagia/efeitos dos fármacos , Temperatura Baixa , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Substâncias Protetoras/farmacologia , Isquemia Quente/métodosRESUMO
BACKGROUND: Hypothermic oxygenated machine perfusion (HOPE) has been shown to improve the quality of liver donation after circulatory death (DCD) compared to cold storage (CS). However, the mechanism by which HOPE works is unclear. In this study, a mouse liver HOPE system was developed to characterize the role of P-selectin in the protective effect of HOPE on DCD livers. METHODS: A warm ischemia model of the liver and an isolated perfused liver system were established to determine a suitable flow rate for HOPE. Perfusate and tissue samples from wild-type and P-selectin knockout (KO) mice were used to determine liver function, apoptosis and necrosis rates, deoxyribonucleic acid injury and oxidative stress levels, leukocyte and endothelial cell activation, and inflammatory reactions. RESULTS: A mouse liver HOPE system was successfully established. HOPE at flow rates between 0.1 and 0.5 mL/min · g were shown to have a protective effect on the DCD liver. P-selectin KO improved the quality of the DCD liver in the CS group, and reduction of P-selectin expression in the wild-type HOPE group had similar protective effects. Moreover, there was a reduction in the degree of oxidative stress and deoxyribonucleic acid injury in the P-selectin KO HOPE group compared with the P-selectin KO CS group. CONCLUSIONS: We established a mouse HOPE system and determined its suitable flow. We also proved that P-selectin deficiency alleviated DCD liver injury. HOPE protected the DCD liver through regulating P-selectin-dependent and -independent pathways.
Assuntos
Aloenxertos/metabolismo , Rejeição de Enxerto/prevenção & controle , Transplante de Fígado/efeitos adversos , Fígado/metabolismo , Perfusão/métodos , Aloenxertos/efeitos dos fármacos , Aloenxertos/patologia , Animais , Isquemia Fria/métodos , Modelos Animais de Doenças , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Hepatócitos , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Knockout , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/administração & dosagem , Selectina-P/genética , Selectina-P/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Isquemia Quente/efeitos adversosRESUMO
The impacts of in-furnace kaolin addition on the formation and emission characteristics of PM2.5 from a 1000 MW coal-fired utility boiler equipped with electrostatic precipitators (ESPs) are investigated for the first time ever in this contribution. Detailed characterization of the chemical composition, micromorphology, melting characteristics of the fine PM, total fly ash, and/or bottom ash samples were carried out using the X-ray fluorescence probe, the field emission scanning electron microscope coupled with an energy dispersive X-ray detector, the ash fusion analyzer, and the dust specific resistivity analyzer. The results showed that the formation of fine PM was reduced when kaolin was added, and the mass concentrations of the particulate matter with the aerodynamic diameters of ≤0.3 and 2.5 µm (PM0.3 and PM2.5) were reduced by 55.97% and 5.48%, respectively. As expected, kaolin reacted with the volatile mineral vapors (e.g., Ca, Na) and inhibited their partitioning into ultrafine PM. It was interesting to find that the added kaolin modified the ash melting behavior, and promoted the capture of the ultrafine PM onto the coarse particles. What is more, the added kaolin reduced the specific resistivity of the fly ash and improved their capture efficiency in the ESPs. Finally, the above combined effects brought about the emission reductions of 41.27% and 36.72% for PM0.3 and PM2.5 after the ESPs. These results provided a direct confirmation on the feasibility of in-furnace kaolin addition on the PM reduction in the realistic combustion conditions.
Assuntos
Poluentes Atmosféricos , Carvão Mineral , Cinza de Carvão , Caulim , Material Particulado , Centrais ElétricasRESUMO
Hypothermic machine perfusion (HMP) has been demonstrated to be a more effective method for preserving livers donated after circulatory death (DCD) than cold storage (CS); however, the underlying mechanisms remain unclear. The aim of the present study was to investigate the protective effects of HMP on rat DCD livers and the possible role of the nuclear factor erythroid 2related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway. A total of 18 adult male rats were randomly divided into three groups: Control, HMP and CS (n=6 per group). To simulate the conditions of DCD liver transplantation, rat livers in the CS and HMP groups were subjected to 30 min warm ischemia following cardiac arrest and were then preserved by CS or HMP for 3 h. Subsequently, after 1 h of isolated reperfusion, the extent of ischemia/reperfusion injury (IRI) and cellular functions were assessed. During reperfusion, intrahepatic resistance and bile production were measured, and the perfusion fluid was collected for liver enzyme analysis. The liver tissues were then harvested for the assessment of malondialdehyde (MDA) production, superoxide dismutase (SOD) activity, ATP levels, as well as for histological analysis, immunohistochemistry and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Finally, the expression levels of the components associated with the Nrf2ARE signaling pathway were analyzed via western blotting and reverse transcriptionquantitative polymerase chain reaction. The results of the present study revealed that, compared with in the CS group, the HMP group exhibited higher levels of ATP, bile production and SOD activity, and improved histological results; however, lower levels of liver enzymes, apoptosis and MDA were detected. Additionally, the findings of the present study also suggested that the Nrf2ARE signaling pathway may be activated by the steady laminar flow of HMP. In conclusion, HMP may attenuate ischemiareperfusion injury to rat DCD livers via activation of the Nrf2ARE signaling pathway.
Assuntos
Morte , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fígado/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Perfusão , Traumatismo por Reperfusão , Transdução de Sinais , Animais , Transplante de Fígado , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controleRESUMO
The protective mechanisms for liver preservation associated with hypothermic machine perfusion (HMP) remain unclear. However, the lack of a common and portable HMP system for rat livers limits the study of HMP. The present study aimed to develop a novel, modified HMP system using a LifePort Kidney Transporter for preserving rat livers. A simple 'Y' shunt combined with a pressoreceptor for flow and pressure regulation was adapted to perfuse rat livers via the portal vein continuously using a LifePort Kidney Transporter under its 'prime mode' setting. An electronic scale was installed under the liver container to calculate the portal inflow according to the association with weight, density and volume of the perfusate. A total of 10 rat livers underwent 6 h of HMP using histidine-tryptophan-ketoglutarate solution enriched with acridine orange (AO) and propidium iodide (PI). The perfusion status of HMP was assessed by comparison of AO+PI-positive cell count in core region (CR) and peripheral region (PR) of rat liver under fluorescence microscopy. The dynamics (inflow, pressure and intrahepatic resistance of perfusion) were assessed to identify whether this system met the demands for HMP of rat livers. Biochemical [alanine transaminase (ALT), lactate dehydrogenase (LDH) and endothelin levels] and histological parameters (sinusoidal dilatation, endothelial cell detachment and vacuolization) were measured to determine cellular damage associated with HMP. No significant difference was observed between the CR and PR according to the comparison of the AO+PI-positive cell count, which indicated that complete perfusion was achieved. Intrahepatic resistance significantly decreased during the initial 3 h of HMP (P<0.01), but remained stable during the final 3 h. ALT and LDH levels significantly increased over the 6 h HMP duration: ALT (0 h, 42.67±5.81 U/l; 3 h, 90.67±6.74 U/l; 6 h, 164.33±7.31 U/l; P<0.01) and LDH (0 h, 492.90±90.20 U/l; 3 h, 973.53±97.4; 6 h, 1,843.40±85.78 U/l; P<0.01) However, the levels of endothelin and oxygen consumption were constant throughout HMP. Furthermore, histological analysis indicated sinusoidal dilation was significantly increased in the post-HMP group compared with the pre-HMP group (P<0.01); however, no other significant differences were observed. Combined with the results of ATP test (640.64±29.46 nmol/l) and bile production (4.88±0.69 µl/h/g of liver) at the end of HMP, the present results demonstrated minimal cellular injury associated with HMP while retaining the dependability and portability of the LifePort Kidney Transporter, which suggests the modified HMP system met the demands required and may be suitable for rat liver preservation.
RESUMO
Mild hypothermia is known to protect against ischemia and reperfusion (IR) injury. The exact mechanisms of the protection are not fully understood. Forkhead box O3 (FOXO3a) has been defined as a critical mediator in cellular processes, including oxidative stress, apoptosis, inflammation, cell death and DNA repair; however, the protection function in mild hypothermia has not been reported previously. The current study was designed to investigate the function of phosphoinositide 3kinase (PI3K)/protein kinase B (AKT)/FOXO3a pathway in pretreatment with mild hypothermia during IR injury. Additionally, PI3K/AKT/FOXO3a signaling was inhibited using Ly294002 and the effect on the protective function of mild hypothermia pretreatment was evaluated. Furthermore, the apoptotic and inflammatory response induced by the IR injury was evaluated. Liver IR injury induced a significant increase in the level of apoptosis and inflammatory responses. However, pretreatment with mild hypothermia increased phospho (p)AKT and pFOXO3a following IR injury, and significantly reduced apoptosis and inflammatory cytokines release. However, inhibiting pAKT and pFOXO3a using Ly294002 suppressed the liver protection produced by mild hypothermia. In conclusion, these findings indicated that mild hypothermia pretreatment exhibited liver protective effects against IR injury associated with suppressing inflammatory cytokine release and apoptosis via the PI3K/AKT/FOXO3a pathway.
Assuntos
Proteína Forkhead Box O3/metabolismo , Hipotermia Induzida , Fígado/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Cromonas/farmacologia , Ensaio de Imunoadsorção Enzimática , Proteína Forkhead Box O3/genética , Interleucina-1beta/sangue , Interleucina-6/sangue , Fígado/metabolismo , Masculino , Morfolinas/farmacologia , NF-kappa B/metabolismo , Peroxidase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangueRESUMO
Excess bilirubin often evokes hepatobiliary system dysfunction. In the present work, we developed an efficient, safe and blood compatible adsorbent for bilirubin removal from human blood. In view of the highly effective adsorption of carbon nanotubes (CNTs) on bilirubin but with many side effects, and good biocompatibility of chitin but with low efficiency for bilirubin removal, new chitin/carbon nanotube (Ch/CNT) nanofibrous microspheres were constructed from chitin solution in NaOH/urea aqueous system by blending with CNTs. The results of AFM, SEM, and TEM demonstrated that the CNTs were dispersed well in the chitin matrix, and the chitin nanofibers intertwined with CNTs to form hybrid chitin/CNT nanofibers and then weaved into a 3D interconnected network architecture. Moreover, lysine (Lys), a highly specific ligand for bilirubin, was immobilized tightly to the hybrid microspheres to obtain Ch/CNT/Lys. The resultant microspheres possessed large surface area and hierarchical pores including mesopores and micropores, which could allow bilirubin to enter easily and store, leading to highly efficient adsorption. The Ch/CNT/Lys microspheres exhibited excellent bilirubin adsorption property (107.2 mg g-1) and efficient bilirubin clearance rate from real hyperbilirubinemia plasma competing with protein, as well as good cell affinity and blood compatibility, as a result of the combination of the high adsorption of CNTs and inherent biocompatibility of chitin and lysine. Therefore, an effective strategy to develop a novel biocompatible and blood compatible bilirubin adsorbent is provided, showing potential applications for hemoperfusion in blood purified therapy.
RESUMO
Between 2010 and 2013, we recorded 66 cases of failed organ donation after brain death (DBD) due to the excessive use of the vasoactive drugs resulting in impaired hepatic and/or renal function. To investigate the effect of extracorporeal membrane oxygenation (ECMO) in donor management, ECMO was used to provide support for DBD donors with circulatory and/or respiratory failure from 2013 to 2015. A retrospective cohort study between circulatory non-stable DBD with vasoactive drugs (DBD-drug) and circulatory non-stable DBD with ECMO (DBD-ECMO) was designed to compare the transplant outcomes. A total of 19 brain death donors were supported by ECMO. The incidence rate of post-transplant liver primary non-function (PNF) was 10% (two of 20) in DBD-drug group and zero in DBD-ECMO group. Kidney function indicators, including creatinine clearance and urine production, were significantly better in DBD-ECMO group, as well as the kidney delayed graft function (DGF) rate was found to be decreased by the use of ECMO in our study. Donation success rate increased steadily from 47.8% in 2011 to 84.6% in 2014 after the ECMO intervention. The use of ECMO in assisting circulatory and respiratory function of DBD can reduce liver and kidney injury from vasoactive drugs, thereby improving organ quality and reducing the organ discard rates.
Assuntos
Morte Encefálica , Função Retardada do Enxerto/prevenção & controle , Oxigenação por Membrana Extracorpórea , Transplante de Rim , Transplante de Fígado , Preservação de Órgãos/métodos , Coleta de Tecidos e Órgãos/métodos , Adulto , Fármacos Cardiovasculares/efeitos adversos , Função Retardada do Enxerto/induzido quimicamente , Dopamina/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/efeitos adversos , Preservação de Órgãos/efeitos adversos , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Coleta de Tecidos e Órgãos/efeitos adversosRESUMO
A neutral exopolysaccharide (EPS), designated LPC-1, was isolated from the culture of Lactobacillus plantarum C88 and purified by ion-exchange and gel-permeation chromatography. LPC-1 had an average molecular weight of 1.15 × 10(6) Da, and it was composed of galactose and glucose with a molar ratio of 1:2. The antioxidant activity of LPC-1 was evaluated with the in vitro scavenging abilities on hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. The results indicated that LPC-1 had good scavenging ability on hydroxyl radicals. Furthermore, the protective effect of LPC-1 on H(2)O(2)-induced Caco-2 cells oxidative injury was investigated. As results, LPC-1 inhibited the formation of malondialdehyde (MDA) and raised the activities of superoxide dismutase (SOD) and total antioxidant capacities (T-AOC) in a dose-dependent manner. These results demonstrate that the EPS from L. plantarum C88 has antioxidant effects that may involve scavenging of reactive oxygen species (ROS), up-regulation of enzymatic and non-enzymatic antioxidant activities, and reduction of lipid peroxidation.
Assuntos
Antioxidantes/farmacologia , Lactobacillus plantarum/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Ácido Ascórbico/farmacologia , Compostos de Bifenilo/química , Células CACO-2 , Cromatografia por Troca Iônica , Sequestradores de Radicais Livres/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Cinética , Malondialdeído/metabolismo , Picratos/química , Padrões de Referência , Superóxido Dismutase/metabolismoRESUMO
Exopolysaccharides (EPSs) produced by lactic acid bacteria (LAB) play an important role in the improvement of the physical properties of fermented dairy products. To find EPS-producing LAB strains with potential industrial applications, a Lactobacillus rhamnosus strain, L. rhamnosus JAAS8, that is capable of producing two forms of EPS when grown in MRS broth or semi-defined medium with glucose as a carbon source was isolated and identified from Chinese sauerkraut. The capsular-polysaccharide (CPS) present surrounding the bacterial surface of L. rhamnosus JAAS8 was observed by both optical microscopy and transmission electron microscopy. The slime-polysaccharide (SPS) present in the growth medium was produced mainly during the exponential growth phase, while the CPS was produced only in fermentation. Monosaccharide analysis of the purified polysaccharide samples showed that the CPS was composed of galactose and N-acetylglucosamine in a molar ratio of 5:1, and the SPS was composed of galactose, glucose and N-acetylglucosamine in a molar ratio of 4:1:1. The use of L. rhamnosus JAAS8 could be considered for potential applications in the dairy industry to improve the rheological properties of fermented milk products by increasing their water-holding capacity and viscosity.