[Effects of resveratrol on inhibiting pyroptosis of intestinal cancer cells].

Objective: To study the effects of resveratrol (Res) on pyroptosis of colorectal cancer cells . Methods: ①The experiment of dextran sodium sulfate (DSS) induced colon cancer (CRC) in mice: 30 C57BL/6 mice were randomly divided into control group, Azoxymethane (AOM) group, AOM/DSS group, AOM/DSS+Res group and Res group, with 6 mice in each group, the modeling cycle was 70 days in total. Mice in AOM group, AOM/DSS group and AOM/DSS+Res group, at the first day of the first week, were intraperitoneally injected with AOM (10 mg/kg) once, and the ordinary chaw was replaced with high iron feed, and sterile water was given, 1% DSS water was given to AOM/DSS group and AOM/DSS+Res group. The mice in AOM/DSS+Res and Res groups were given resveratrol (50 mg/kg) by oral gavage, When the mold was finished, colon tissue of mice was fixed, embedded and sectionalized. The expressions of NLRP3, Caspase-1 and IL-18 in colon tissues of mice were detected by IHC and Western blot. ②In vitro experiment: HCT 116 cells were given Res (2.4 µg/L) and transfected with miR-31. The Res was divided into 4 groups and labeled with 0 h, 12 h, 24 h and 48 h respectively. The transfected cells were divided into 5 groups: Control group, miR-31 mimic group, miR-31 mimic + Res group, miR-31 inhibitor group, miR-31 inhibitor + Res group. The protein expressions of NLRP3, Caspase-1, GSDMD-N, IL-18 and IL-1ß were detected by Western blot. Results: Animal experiments: Compared with control group, the protein expressions of NLRP3, Caspase-1 and IL-18 in AOM/DSS group were increased significantly (P<0.01). The protein expression levels of NLRP3, Caspase-1 and IL-18 in AOM/DSS+Res group were significantly lower than those in AOM/DSS group (P<0.01). Cell experiments: Compared with the control group, the protein expressions of NLRP3 (P<0.01), GSDMD-N (P<0.05) and IL-18 (P< 0.01) in miR-31 mimic group were increased significantly. The protein expressions of NLRP3, GSDMD-N and IL-18 in miR-31 inhibitor group were decreased significantly (P<0.05). Conclusion: Res inhibited the pyroptosis of colorectal cancer cells through pyroptosis.

Complex Flavanones from Cryptocarya metcalfiana and Structural Revision of Oboflavanone A.

Nine new complex flavanones, cryptometcones A-I (1-9), along with four known analogues, were isolated from Cryptocarya metcalfiana. The structures of 1-9 including their absolute configurations were elucidated by spectroscopic data analysis and electronic circular dichroism (ECD) calculations. In addition, the structure of oboflavanone A was revised, while the absolute configurations of oboflavanone B, cryptoflavanone C, and cryptoflavanone D were determined, according to their spectroscopic data. Compounds 3-5, 8, and 9 exhibited cytotoxicity against the HCT-116 cancer cell line.

Impact of Tumor Barriers on Nanoparticle Delivery to Macrophages.

The delivery of therapeutic nanoparticles to target cells is critical to their effectiveness. Here we quantified the impact of biological barriers on the delivery of nanoparticles to macrophages in two different tissues. We compared the delivery of gold nanoparticles to macrophages in the liver versus those in the tumor. We found that nanoparticle delivery to macrophages in the tumor was 75% less than to macrophages in the liver due to structural barriers. The tumor-associated macrophages took up more nanoparticles than Kupffer cells in the absence of barriers. Our results highlight the impact of biological barriers on nanoparticle delivery to cellular targets.

FX5, a non-steroidal glucocorticoid receptor antagonist, ameliorates diabetic cognitive impairment in mice.

Diabetic cognitive impairment (DCI) is a common diabetic complication characterized by learning and memory deficits. In diabetic patients, hyperactivated hypothalamic-pituitary-adrenal (HPA) axis leads to abnormal increase of glucocorticoids (GCs), which causes the damage of hippocampal neurons and cognitive impairment. In this study we investigated the cognition-improving effects of a non-steroidal glucocorticoid receptor (GR) antagonist 5-chloro-N-[4-chloro-3-(trifluoromethyl) phenyl]thiophene-2-sulfonamide (FX5) in diabetic mice. Four weeks after T1DM or T2DM was induced, the mice were administered FX5 (20, 40 mg·kg-1·d-1, i.g.) for 8 weeks. Cognitive impairment was assessed in open field test, novel object recognition test, Y-maze test, and Morris water maze test. We showed that FX5 administration significantly ameliorated the cognitive impairments in both type 1 and 2 diabetic mice. Similar cognitive improvement was observed in diabetic mice following brain GR-specific knockdown by injecting AAV-si-GR. Moreover, AAV-si-GR injection occluded the cognition-improving effects of FX5, suggesting that FX5 functioning as a non-steroidal GR antagonist. In PA-treated primary neurons (as DCI model in vitro), we demonstrated that FX5 (2, 5, 10 µM) dose-dependently ameliorated synaptic impairment via upregulating GR/BDNF/TrkB/CREB pathway, protected against neuronal apoptosis through repressing GR/PI3K/AKT/GSK3ß-mediated tauopathy and subsequent endoplasmic reticulum stress. In LPS-treated primary microglia, FX5 dose-dependently inhibited inflammation through GR/NF-κB/NLRP3/ASC/Caspase-1 pathway. These beneficial effects were also observed in the hippocampus of diabetic mice following FX5 administration. Collectively, we have elucidated the mechanisms underlying the beneficial effects of non-steroidal GR antagonist FX5 on DCI and highlighted the potential of FX5 in the treatment of the disease.

A Polysaccharide From the Whole Plant of Plantago asiatica L. Enhances the Antitumor Activity of Dendritic Cell-Based Immunotherapy Against Breast Cancer.

Dendritic cells (DCs) are the most potent professional antigen-presenting cells (APCs) that mediate T-cell immune responses. Breast cancer is one of the most commonly diagnosed diseases and its mortality rate is higher than any other cancer in both humans and canines. Plantain polysaccharide (PLP), extracted from the whole plant of Plantago asiatica L., could promote the maturation of DCs. In this research, we found that PLP could upregulate the maturation of DCs both in vitro and in vivo. PLP-activated DCs could stimulate lymphocytes' proliferation and differentiate naive T cells into cytotoxic T cells. Tumor antigen-specific lymphocyte responses were enhanced by PLP and CIPp canine breast tumor cells lysate-pulsed DCs, and PLP and CIPp-cell-lysate jointly stimulated DCs cocultured with lymphocytes having the great cytotoxicity on CIPp cells. In the 4T1 murine breast tumor model, PLP could control the size of breast tumors and improve immunity by recruiting DCs, macrophages, and CD4+ and CD8+ T cells in the tumor microenvironment. These results indicated that PLP could achieve immunotherapeutic effects and improve immunity in the breast tumor model.

Iridoid Constituents of Viburnum brachybotryum.

Eleven new iridoids, brachybones A-K (1-11), were isolated from the twigs of Viburnum brachybotryum. Their structures including absolute configurations were determined by spectroscopic data analysis and from the electronic circular dichroism (ECD) spectra. All of the compounds 1-11 possess one or two acetoxysenecioate substituents. Furthermore, compounds 5-7 and 11 feature a Cl atom in the molecule, while compounds 9-11 exhibit a cagelike rigid skeleton through an unusual oxo bridge from C-3 to C-8 or C-10. The isolates were evaluated for cytotoxic activity against the HCT-116, A549, and Hela cell lines, and the results showed compounds 10 and 11 to be active against HCT-116 cells.

HMGB1 signaling-regulated endoplasmic reticulum stress mediates intestinal ischemia/reperfusion-induced acute renal damage.

BACKGROUND: Ischemia/reperfusion of the intestine often leads to distant organ injury, but the mechanism of intestinal ischemia/reperfusion-induced renal dysfunction is still not clear. The present study aimed to investigate the mechanisms of acute renal damage after intestinal ischemia/reperfusion challenge and explore the role of released high-mobility group box-1 in this process. METHODS: Intestinal ischemia/reperfusion was induced in male Sprague-Dawley rats by clamping the superior mesenteric artery for 1.5 hours. At different reperfusion time points, anti-high-mobility group box-1 neutralizing antibodies or ethyl pyruvate were administered to neutralize or inhibit circulating high-mobility group box-1, respectively. RESULTS: Significant kidney injury was observed after 6 hours of intestinal reperfusion, as indicated by increased serum levels of urea nitrogen and creatinine, increased expression of neutrophil gelatinase-associated lipocalin, interleukin-6, and MIP-2, and enhanced cell apoptosis, as indicated by cleaved caspase 3 levels in renal tissues. The levels of phosphorylated eIF2ɑ, activating transcription factor 4, and C/EBP-homologous protein (CHOP) were markedly elevated, indicating the activation of endoplasmic reticulum stress in the impaired kidney. High-mobility group box-1 translocated to cytoplasm in the intestine and serum concentrations of high-mobility group box-1 increased notably during the reperfusion phase. Both anti-high-mobility group box-1 antibodies and ethyl pyruvate treatment significantly reduced serum high-mobility group box-1 concentrations, attenuated endoplasmic reticulum stress in renal tissue and inhibited the development of renal damage. Moreover, the elevated expression of receptor for advanced glycation end products in the kidneys after intestinal ischemia/reperfusion was abrogated after high-mobility group box-1 inhibition. CONCLUSION: These results suggested that high-mobility group box-1 signaling regulated endoplasmic reticulum stress and promoted intestinal ischemia/reperfusion-induced acute kidney injury. High-mobility group box-1 neutralization/inhibition might serve as a pharmacological intervention strategy for these pathophysiological processes.

The dose threshold for nanoparticle tumour delivery.

Nanoparticle delivery to solid tumours over the past ten years has stagnated at a median of 0.7% of the injected dose. Varying nanoparticle designs and strategies have yielded only minor improvements. Here we discovered a dose threshold for improving nanoparticle tumour delivery: 1 trillion nanoparticles in mice. Doses above this threshold overwhelmed Kupffer cell uptake rates, nonlinearly decreased liver clearance, prolonged circulation and increased nanoparticle tumour delivery. This enabled up to 12% tumour delivery efficiency and delivery to 93% of cells in tumours, and also improved the therapeutic efficacy of Caelyx/Doxil. This threshold was robust across different nanoparticle types, tumour models and studies across ten years of the literature. Our results have implications for human translation and highlight a simple, but powerful, principle for designing nanoparticle cancer treatments.

Suppressing Subcapsular Sinus Macrophages Enhances Transport of Nanovaccines to Lymph Node Follicles for Robust Humoral Immunity.

Nanovaccines need to be transported to lymph node follicles to induce humoral immunity and generate neutralizing antibodies. Here, we discovered that subcapsular sinus macrophages play a barrier role to prevent nanovaccines from accessing lymph node follicles. This is illustrated by measuring the humoral immune responses after removing or functionally altering these cells in the nanovaccine transport process. We achieved up to 60 times more antigen-specific antibody production after suppressing subcapsular sinus macrophages. The degree of the enhanced antibody production is dependent on the nanovaccine dose and size, formulation, and administration time. We further found that pharmacological agents that disrupt the macrophage uptake function can be considered as adjuvants in vaccine development. Immunizing mice using nanovaccines formulated with these agents can induce more than 30 times higher antigen-specific antibody production compared to nanovaccines alone. These findings suggest that altering transport barriers to enable more of the nanovaccine to be delivered to the lymph node follicles for neutralizing antibody production is an effective strategy to boost vaccination.

Effect of volatile anesthetics on mortality and clinical outcomes in patients undergoing coronary artery bypass grafting: a meta-analysis of randomized clinical trials.

INTRODUCTION: It remains unclear whether intraoperative use of volatile anesthetics has a positive effect on postoperative clinical outcomes in patients undergoing coronary artery bypass grafting (CABG). Therefore, we aimed to systematically analyze the long- and short-term mortality rates and the clinical outcomes of volatile anesthesia compared to those of total intravenous anesthesia (TIVA) in patients undergoing CABG. EVIDENCE ACQUISITION: We queried the MEDLINE, Embase, and CENTRAL databases from inception to October 2019 for relevant randomized clinical trials (RCTs) on the intraoperative use of volatile anesthetics in patients undergoing CABG. EVIDENCE SYNTHESIS: We pooled and analyzed 36 eligible RCTs with 10,308 patients and found that there was no significant difference in the long- and short-term mortality rate between the use of volatile anesthesia and TIVA during CABG. 30-day mortality, volatile group (39/2,824, 1.4%) vs. TIVA group (35/2,786, 1.3%), RR=1.11, 95% CI [0.70, 1.74], P value for effect =0.66, I2=0%, moderate-certainty evidence; One-year mortality, volatile group (77/2,749, 2.8%) vs. TIVA group (78/2,731, 2.9%), RR=0.98, 95% CI [0.72, 1.34], P value for effect =0.90, I2=0%, moderate-certainty evidence. Mechanical ventilation time was reduced in volatile group (MD -0.65, 95% CI [-1.07, -0.24], P value for effect =0.002, I2=26%). CONCLUSIONS: There is no difference in the long- and short-term mortality and clinical outcomes between intraoperative use of volatile anesthetics and TIVA during CABG. However, volatile anesthetics may shorten the mechanical ventilation time. There is a need for high-quality multicenter RCTs that specifically assess factors that influence mortality and clinical outcomes.

[Common cancer genetic analysis methods and application study based on TCGA database].

The development of second-generation sequencing (NGS) technology is providing numerous data which shifts the focus of cancer research from the sequencing of multi-species to the analysis and comparison of select data via high-throughput sequencing. The NGS also facilitates the diversity of available genetic data analysis methods, the constant optimization and innovation of analytical approaches for high-throughput genomics as well as the rapid development of genetic data mining and analysis models. The Cancer Genome Atlas (TCGA) database is a direct result of this work. The TCGA database provides a comprehensive record of genetic data collected from a tumor patient's sample, including its DNA sequence, transcriptional information, epigenetic modification and related. This review elaborates the latest progress in both the mining algorithm and analysis methods for tumor genomics. Specially, we introduce and review the TCGA database and data analysis approaches while demonstrating its applicability using representative cases. This review may shed light on new tumor-related targets discovery for researchers by means of bid data.

Small molecule IVQ, as a prodrug of gluconeogenesis inhibitor QVO, efficiently ameliorates glucose homeostasis in type 2 diabetic mice.

Gluconeogenesis is a major source of hyperglycemia in patients with type 2 diabetes mellitus (T2DM), thus targeting gluconeogenesis to suppress glucose production is a promising strategy for anti-T2DM drug discovery. In our preliminary in vitro studies, we found that a small-molecule (E)-3-(2-(quinoline-4-yl)vinyl)-1H-indol-6-ol (QVO) inhibited the hepatic glucose production (HGP) in primary hepatocytes. We further revealed that QVO suppressed hepatic gluconeogenesis involving calmodulin-dependent protein kinase kinase ß- and liver kinase B1-adenosine monophosphate-activated protein kinase (AMPK) pathways as well as AMPK-independent mitochondrial function-related signaling pathway. To evaluate QVO's anti-T2DM activity in vivo, which was impeded by the complicated synthesis route of QVO with a low yield, we designed and synthesized 4-[2-(1H-indol-3-yl)vinyl]quinoline (IVQ) as a prodrug with easier synthesis route and higher yield. IVQ did not inhibit the HGP in primary hepatocytes in vitro. Pharmacokinetic studies demonstrated that IVQ was quickly converted to QVO in mice and rats following administration. In both db/db and ob/ob mice, oral administration of IVQ hydrochloride (IVQ-HCl) (23 and 46 mg/kg every day, for 5 weeks) ameliorated hyperglycemia, and suppressed hepatic gluconeogenesis and activated AMPK signaling pathway in the liver tissues. Furthermore, IVQ caused neither cardiovascular system dysfunction nor genotoxicity. The good druggability of IVQ has highlighted its potential in the treatment of T2DM and the prodrug design for anti-T2DM drug development.

Downregulated expression of microRNA-329 inhibits apoptosis of nigral dopaminergic neurons by regulating CDKN2D expression via the FoxO3a signaling pathway in rats with Parkinson's disease.

Parkinson's disease (PD) is a common neurodegenerative disorder due to the loss of dopaminergic neurons in the substantia nigra. This study focuses on the effect of microRNA-329 (miR-329) on nigral dopaminergic neurons in a rat model of PD via the FoxO3a signaling pathway by binding to CDKN2D. Brain tissues from the substantia nigra were taken from the rats in two groups. TUNEL staining was used to observe tyrosine hydroxylase (TH)-positive neurons. Nigral dopaminergic neurons were randomized into the normal, blank, negative control (NC), miR-329 mimics, miR-329 inhibitors, small interfering (siRNA)-CDKN2D, and miR-329 inhibitors + siRNA-CDKN2D groups. Expressions of miR-329, CDKN2D, FoxO3a, AKT, caspase-3 and Bcl-2 were determined using RT-qPCR and western blotting. Apoptosis rate of nigral dopaminergic neurons in 7 groups was determined by flow cytometry. Compared with the blank and NC groups, the miR-329 mimics group showed increased miR-329 and caspase-3 expressions as well as decreased expressions of CDKN2D, FoxO3a, AKT, and Bcl-2, the siRNA-CDKN2D group indicated enhanced expressions of caspase-3 and declined expressions of CDKN2D, FoxO3a, AKT, and Bcl-2, and the miR-329 inhibitors group revealed decreased miR-329 and caspase-3 expressions and increased expressions of CDKN2D, FoxO3a, AKT, and Bcl-2. The apoptosis rate of nigral dopaminergic neurons was significantly increased in the miR-329 mimics and siRNA-CDKN2D groups, but was decreased in the miR-329 inhibitors group. Our data suggested that downregulated miR-329 could inhibit apoptosis of nigral dopaminergic neurons in a rat model of PD by upregulating the expression of CDKN2D via the activation of the FoxO3a signaling pathway.

Blood-brain barrier permeability and neuroprotective effects of three main alkaloids from the fruits of Euodia rutaecarpa with MDCK-pHaMDR cell monolayer and PC12 cell line.

The fruits of Euodia rutaecarpa (Euodiae Fructus, EF), the widely used traditional Chinese medicine, have various central nervous system effects. Alkaloids following as evodiamine (EDM), rutaecarpine (RCP) and dehydroevodiamine (DEDM) are the major substances in EF. The MDCK-pHaMDR cell monolayer model was utilized as a blood-brain barrier (BBB) surrogate model to study their BBB permeability. The transport samples were analyzed by high performance liquid chromatography and the apparent permeability coefficients (Papp) were calculated. EDM and RCP showed high permeability through BBB by passive diffusion, while DEDM showed moderate permeability with efflux mechanism related to P-glycoprotein (P-gp). EDM and RCP could also reduce the efflux of DEDM probably by inhibiting P-gp. The neuroprotective effects of the three alkaloids were then studied on the PC12 cell line injured by 1-methyl-4-phenylpyridinium ion (MPP+) or hydrogen peroxide (H2O2). EDM could significantly reduce MPP+ or H2O2-induced cell injury dose-dependently. RCP could increase the cell viability in MPP+ treated group while DEDM showed a protective effect against H2O2 injury. This study predicted the permeability of EDM, RCP and DEDM through BBB and discovered the neuroprotective substance basis of EF as a potential encephalopathy drug.

Effect of removing Kupffer cells on nanoparticle tumor delivery.

A recent metaanalysis shows that 0.7% of nanoparticles are delivered to solid tumors. This low delivery efficiency has major implications in the translation of cancer nanomedicines, as most of the nanomedicines are sequestered by nontumor cells. To improve the delivery efficiency, there is a need to investigate the quantitative contribution of each organ in blocking the transport of nanoparticles to solid tumors. Here, we hypothesize that the removal of the liver macrophages, cells that have been reported to take up the largest amount of circulating nanoparticles, would lead to a significant increase in the nanoparticle delivery efficiency to solid tumors. We were surprised to discover that the maximum achievable delivery efficiency was only 2%. In our analysis, there was a clear correlation between particle design, chemical composition, macrophage depletion, tumor pathophysiology, and tumor delivery efficiency. In many cases, we observed an 18-150 times greater delivery efficiency, but we were not able to achieve a delivery efficiency higher than 2%. The results suggest the need to look deeper at other organs such as the spleen, lymph nodes, and tumor in mediating the delivery process. Systematically mapping the contribution of each organ quantitatively will allow us to pinpoint the cause of the low tumor delivery efficiency. This, in effect, enables the generation of a rational strategy to improve the delivery efficiency of nanoparticles to solid tumors either through the engineering of multifunctional nanosystems or through manipulation of biological barriers.

Cancer-on-a-chip systems at the frontier of nanomedicine.

Nanomedicine provides a unique opportunity for promoting drug efficacy through enhanced delivery mechanisms. However, its translation into the clinics has been relatively slow compared with the large amount of research occurring in laboratory settings. Given the limitations of conventional cell culture models and preclinical animal models, we discuss the potential utility of recently developed cancer-on-a-chip platforms, which maximally replicate the pathophysiology of the human tumor microenvironments, as alternatives for effective evaluation of nanomedicine. We begin with a brief discussion of nanomedicine, then chart the history of organ-on-a-chip platform development and their recent evolution as tools for modeling different cancers for assessing nanomedicine efficacy, concluding with future perspectives for the field.

Comparison of different methods of splenic hilar lymph node dissection for advanced upper- and/or middle-third gastric cancer.

BACKGROUND: Surgery for advanced gastric cancer (AGC) often includes dissection of splenic hilar lymph nodes (SHLNs). This study compared the safety and effectiveness of different approaches to SHLN dissection for upper- and/or middle-third AGC. METHODS: We retrospectively compared and analyzed clinicopathologic and follow-up data from a prospectively collected database at the Peking University Cancer Hospital. Patients were divided into three groups: in situ spleen-preserved, ex situ spleen-preserved and splenectomy. RESULTS: We analyzed 217 patients with upper- and/or middle-third AGC who underwent R0 total or proximal gastrectomy with splenic hilar lymphadenectomy from January 2006 to December 2011, of whom 15.2 % (33/217) had metastatic SHLNs, and from whom 11.4 % (53/466) of the dissected SHLNs were metastatic. The number of harvested SHLNs per patient was higher in the ex situ group than in the in situ group (P = 0.017). Length of postoperative hospital stay was longer in the splenectomy group than in the in situ group (P = 0.002) or the ex situ group (P < 0.001). The splenectomy group also lost more blood volume (P = 0.007) and had a higher postoperative complication rate (P = 0.005) than the ex situ group. Kaplan-Meier (log rank test) analysis showed significant survival differences among the three groups (P = 0.018). Multivariate analysis showed operation duration (P = 0.043), blood loss volume (P = 0.046), neoadjuvant chemotherapy (P = 0.005), and N stage (P < 0.001) were independent prognostic factors for survival. CONCLUSIONS: The ex situ procedure was more effective for SHLN dissection than the in situ procedure without sacrificing safety, whereas splenectomy was not more effective, and was less safe. The SHLN dissection method was not an independent risk factor for survival in this study.

Nanoparticle-liver interactions: Cellular uptake and hepatobiliary elimination.

30-99% of administered nanoparticles will accumulate and sequester in the liver after administration into the body. This results in reduced delivery to the targeted diseased tissue and potentially leads to increased toxicity at the hepatic cellular level. This review article focuses on the inter- and intra-cellular interaction between nanoparticles and hepatic cells, the elimination mechanism of nanoparticles through the hepatobiliary system, and current strategies to manipulate liver sequestration. The ability to solve the "nanoparticle-liver" interaction is critical to the clinical translation of nanotechnology for diagnosing and treating cancer, diabetes, cardiovascular disorders, and other diseases.

A Highly Elastic and Rapidly Crosslinkable Elastin-Like Polypeptide-Based Hydrogel for Biomedical Applications.

Elastin-like polypeptides (ELPs) are promising for biomedical applications due to their unique thermoresponsive and elastic properties. ELP-based hydrogels have been produced through chemical and enzymatic crosslinking or photocrosslinking of modified ELPs. Herein, a photocrosslinked ELP gel using only canonical amino acids is presented. The inclusion of thiols from a pair of cysteine residues in the ELP sequence allows disulfide bond formation upon exposure to UV light, leading to the formation of a highly elastic hydrogel. The physical properties of the resulting hydrogel such as mechanical properties and swelling behavior can be easily tuned by controlling ELP concentrations. The biocompatibility of the engineered ELP hydrogels is shown in vitro as well as corroborated in vivo with subcutaneous implantation of hydrogels in rats. ELP constructs demonstrate long-term structural stability in vivo, and early and progressive host integration with no immune response, suggesting their potential for supporting wound repair. Ultimately, functionalized ELPs demonstrate the ability to function as an in vivo hemostatic material over bleeding wounds.

Effects of sevoflurane before cardiopulmonary bypass on cerebral oxygen balance and early postoperative cognitive dysfunction.

Postoperative cognitive dysfunction (POCD) is associated with cardiopulmonary bypass (CPB). We investigated the effect of different doses of inhaled sevoflurane administered prior to CPB on cerebral oxygen supply and demand, and the incidence of associated early POCD. One hundred and twenty patients were randomly allocated into four treatment groups (n = 30, each) and administered a high- [1.5 minimum alveolar concentration (MAC)], moderate- (1.0 MAC), low- (0.5 MAC), or no- sevoflurane dose prior to CPB. Standard blood gas parameters, serum S-100 protein, and neuron-specific enolase (NSE) were measured at different time points. The mini-mental state examination (MMSE) was administered 1 day before and 24 and 72 h after surgery. The jugular bulb venous oxygen saturation (SjvO2) in the moderate- and high-dose groups at a nasopharyngeal temperature of 25-28 °C was significantly higher compared with the control group, while the arteriovenous oxygen content difference (AVDO2) and cerebral extraction of oxygen (CEO2) were significantly reduced. The serum S-100 protein and NSE concentrations of the moderate- and high-dose groups at 1 and 6 h after the cessation of CPB were significantly lower than that of the control group. The 24 h postoperative MMSE scores of the moderate- and high-dose groups were significantly higher than those of the low-dose and control groups. An inhaled optimal concentration of sevoflurane may be beneficial for cerebral oxygen balance during CPB, and may ameliorate cognitive damage. However, the effect is dose-dependent.