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Acetic acid, as one of the top 50 important chemicals, has been broadly applied for production of cellulose acetate, polyvinyl acetate, as well as synthetic fibers and fabrics, and so on. However, the acetic acid production always involves in water which should be removed. Thus, energy-efficient and environmental-friendly dehydration of acetic acid is highly required in current chemical industry. In this study, we proposed a 'hard-crosslinking-soft' strategy to construct a kind of organic-inorganic hybrid membrane by doping aminated silica (SiO 2 –NH 2) nanoparticles into the polyelectrolyte complex (PEC) membrane for dehydration of acetic acid. The addition of SiO 2 –NH 2 nanoparticles plays two roles: one is as the 'hard' part to overcome the over-swelling issue of 'soft' PEC membrane; another is creation of more free volume for water passing through. As a result, the proposed hybrid membrane could simultaneously augment the permeability and selectivity of the pervaporation membrane, breaking the notorious 'trade-off' restriction of separation membranes. The preparation parameters and operation condition on the performance of the membrane were detailed studied. The optimized membrane offers a flux of 1225 g/m2h and a separation factor of 1442 in dehydration of 10 wt% water/acetic acid mixtures at 50 °C, with pervaporation separation index of 1.77 × 106 g/m2h, among the top-tier separation performance. Besides, the prepared membrane could stably work for 144 h due to the chemical crosslinking by glyoxal, promising for the practical application for acetic acid dehydration. [Display omitted] • A novel kind of organic-inorganic hybrid membrane was constructed by a 'hard-crosslinking-soft' strategy. • The 'hard' nanoparticles inhibit the over-swelling of 'soft' membrane, improving the membrane robustness. • The incorporation of SiO 2 -NH 2 realized 2-fold and 1.5-fold enhancement in separation factor and permeability. • The optimized membrane could continuously and stably work for 144 h without performance degradation. [ABSTRACT FROM AUTHOR]

Short-duration rainstorm, the main cause of urban waterlogging and mountain torrents, is characterized by sudden, intense, and highly destructive rainfall. Understanding the dynamic temporal and spatial distribution patterns of short-duration rainstorm can help to predict their development processes. In this study, the dynamic temporal and spatial distribution models of various types of short-duration rainstorm events were established by using machine learning (ML) method based on the rainfall data of the recent decade in a Chinese coastal megacity, Shenzhen. The dynamic characteristics of these rainstorm events were extracted by using ML method in conjunction with the Locally Linear Embedding algorithm, which shows a potential capability to predict the developmental trend of a heavy rainstorm before it occurs. Based on the method put forward in the current study, characteristic rainfall process models consistent with the local temporal and spatial distribution characteristics of rainstorms can be designed, which is important to understand the risks of the rainstorms and consequently helpful for the assessment of urban flood insurance, the scientific design of drainage systems and the forecasting and warning of urban waterlogging. • ML is used to establish characteristic models for short-duration rainstorm. • The models can describe the dynamic temporal-spatial distribution of rainfall. • There are three short-duration rainstorm models in Shenzhen. [ABSTRACT FROM AUTHOR]

Building up selective mass transfer channels in polymeric membranes is a promising strategy to fabricate effective separation membranes. Herein, a thioether-functionalized hydrazone-linked covalent organic framework, COF-LZU8, pre-modified by Ag ion, was incorporated for constructing aromatic selective channels within a commercial poly (ether-block amide) (Pebax 2533) membrane. The inside nanochannels of resulting membrane were effectively confirmed by measuring the affinity and the selective free volume to toluene via quartz crystal microbalance and low-field nuclear magnetic resonance. Owing to the selective channels, the Ag–COF-LZU8/Pebax membrane presented a considerably enhanced performance for toluene/n-heptane separation comparing with pristine Pebax membranes. The optimized membrane could perform a permeation flux of 293 g/m2h and a separation factor of 4.03 for the separation of 50 wt% toluene/n-heptane mixture. Mixed matrix membranes have been fabricated by introducing an Ag+ ion modified COF-LZU8 into poly (ether-block amide) (Pebax 2533) matrix. With this strategy, toluene perm-selective mass transfer channels were successfully constructed in the Ag–COF-LZU8/Pebax hybrid membrane, owing to the d-π and π-π conjugation interaction between Ag–COF-LZU8 and toluene. Image 1 • Modified COFs/Pebax MMMs were fabricated to separate aromatic/aliphatic mixture. • The optimized COFs/Pebax membrane showed desirable pervaporation performance. • Toluene-permselective channels were built up via the introducing of modified COFs. • These channels were further confirmed by measuring the affinity and selective free volume. [ABSTRACT FROM AUTHOR]

Objective: Breast cancer has become the most prevalent malignant tumor in women, and the occurrence of distant metastasis signifies a poor prognosis. Utilizing predictive models to forecast distant metastasis in breast cancer presents a novel approach. This study aims to utilize readily available clinical data and advanced machine learning algorithms to establish an accurate clinical prediction model. The overall objective is to provide effective decision support for clinicians., Methods: Data from 239 patients from two centers were analyzed, focusing on clinical blood biomarkers (tumor markers, liver and kidney function, lipid profile, cardiovascular markers). Spearman correlation and the least absolute shrinkage and selection operator regression were employed for feature dimension reduction. A predictive model was built using LightGBM and validated in training, testing, and external validation cohorts. Feature importance correlation analysis was conducted on the clinical model and the comprehensive model, followed by univariate and multivariate regression analysis of these features., Results: Through internal and external validation, we constructed a LightGBM model to predict de novo bone metastasis in newly diagnosed breast cancer patients. The area under the receiver operating characteristic curve values of this model in the training, internal validation test, and external validation test1 cohorts were 0.945, 0.892, and 0.908, respectively. Our validation results indicate that the model exhibits high sensitivity, specificity, and accuracy, making it the most accurate model for predicting bone metastasis in breast cancer patients. Carcinoembryonic Antigen, creatine kinase, albumin-globulin ratio, Apolipoprotein B, and Cancer Antigen 153 (CA153) play crucial roles in the model's predictions. Lipoprotein a, CA153, gamma-glutamyl transferase, α-Hydroxybutyrate dehydrogenase, alkaline phosphatase, and creatine kinase are positively correlated with breast cancer bone metastasis, while white blood cell ratio and total cholesterol are negatively correlated., Conclusion: This study successfully utilized clinical blood biomarkers to construct an artificial intelligence model for predicting distant metastasis in breast cancer, demonstrating high accuracy. This suggests potential clinical utility in predicting and identifying distant metastasis in breast cancer. These findings underscore the potential prospect of developing economically efficient and readily accessible predictive tools in clinical oncology., (© 2024. The Author(s).)

Organic solvent nanofiltration (OSN) plays important roles in pharmaceutical ingredients purification and solvent recovery. However, the low organic solvent permeance under cross-flow operation of OSN membrane hampers their industrial applications. Herein, we report the construction of coffee-ring structured membrane featuring high OSN permeance. A water-insoluble crystal monomer that dissolved in EtOH/H 2 O mixed solvent was designed to react with trimesoyl chloride via interfacial polymerization. Owing to the diffusion of EtOH to n-hexane, coffee-ring nanostructure on the support membrane appeared, which served as the template for construction of coffee-ring structured membrane. The optimal nanostructured membrane demonstrated 2.6-fold enhancement in the effective surface area with reduced membrane thickness. Resultantly, the membrane afforded a 2.7-fold enhancement in organic solvent permeance, e.g., ~13 LMH/bar for MeOH, without sacrificing the rejection ability. Moreover, due to the rigid monomer structure, the fabricated membrane shows distinctive running stability in active pharmaceutical ingredients purification and the ability for concentration of medicines., (© 2024 Wiley-VCH GmbH.)

Breast cancer metastasis significantly impacts women's health globally. This study aimed to construct predictive models using clinical blood markers and ultrasound data to predict distant metastasis in breast cancer patients, ensuring clinical applicability, cost-effectiveness, relative non-invasiveness, and accessibility of these models. Analysis was conducted on data from 416 patients across two centers, focusing on clinical blood markers (tumor markers, liver and kidney function indicators, blood lipid markers, cardiovascular biomarkers) and maximum lesion diameter from ultrasound. Feature reduction was performed using Spearman correlation and LASSO regression. Two models were built using LightGBM: a clinical model (using clinical blood markers) and a combined model (incorporating clinical blood markers and ultrasound features), validated in training, internal test, and external validation (test1) cohorts. Feature importance analysis was conducted for both models, followed by univariate and multivariate regression analyses of these features. The AUC values of the clinical model in the training, internal test, and external validation (test1) cohorts were 0.950, 0.795, and 0.883, respectively. The combined model showed AUC values of 0.955, 0.835, and 0.918 in the training, internal test, and external validation (test1) cohorts, respectively. Clinical utility curve analysis indicated the combined model's superior net benefit in identifying breast cancer with distant metastasis across all cohorts. This suggests the combined model's superior discriminatory ability and strong generalization performance. Creatine kinase isoenzyme (CK-MB), CEA, CA153, albumin, creatine kinase, and maximum lesion diameter from ultrasound played significant roles in model prediction. CA153, CK-MB, lipoprotein (a), and maximum lesion diameter from ultrasound positively correlated with breast cancer distant metastasis, while indirect bilirubin and magnesium ions showed negative correlations. This study successfully utilized clinical blood markers and ultrasound data to develop AI models for predicting distant metastasis in breast cancer. The combined model, incorporating clinical blood markers and ultrasound features, exhibited higher accuracy, suggesting its potential clinical utility in predicting and identifying breast cancer distant metastasis. These findings highlight the potential prospects of developing cost-effective and accessible predictive tools in clinical oncology., (© 2024. The Author(s).)

Objective: This study aims to develop an artificial intelligence model utilizing clinical blood markers, ultrasound data, and breast biopsy pathological information to predict the distant metastasis in breast cancer patients., Methods: Data from two medical centers were utilized, Clinical blood markers, ultrasound data, and breast biopsy pathological information were separately extracted and selected. Feature dimensionality reduction was performed using Spearman correlation and LASSO regression. Predictive models were constructed using LR and LightGBM machine learning algorithms and validated on internal and external validation sets. Feature correlation analysis was conducted for both models., Results: The LR model achieved AUC values of 0.892, 0.816, and 0.817 for the training, internal validation, and external validation cohorts, respectively. The LightGBM model achieved AUC values of 0.971, 0.861, and 0.890 for the same cohorts, respectively. Clinical decision curve analysis showed a superior net benefit of the LightGBM model over the LR model in predicting distant metastasis in breast cancer. Key features identified included creatine kinase isoenzyme (CK-MB) and alpha-hydroxybutyrate dehydrogenase., Conclusion: This study developed an artificial intelligence model using clinical blood markers, ultrasound data, and pathological information to identify distant metastasis in breast cancer patients. The LightGBM model demonstrated superior predictive accuracy and clinical applicability, suggesting it as a promising tool for early diagnosis of distant metastasis in breast cancer., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhang, Tan, Huang, Tan, Zhang, Chen and Wei.)

Conductive polymers are recognized as ideal candidates for the development of noninvasive and wearable sensors for real-time monitoring of potassium ions (K + ) in sweat to ensure the health of life. However, the low ion-to-electron transduction efficiency and limited active surface area hamper the development of high-performance sensors for low-concentration K + detection in the sweat. Herein, a wearable K + sensor is developed by tailoring the nanostructure of polypyrrole (PPy), serving as an ion-to-electron transduction layer, for accurately and stably tracing the K + fluctuation in human sweat. The PPy nanostructures can be tailored from nanospheres to nanofibers by controlling the supramolecular assembly process during PPy polymerization. Resultantly, the ion-to-electron transduction efficiency (17-fold increase in conductivity) and active surface area (1.3-fold enhancement) are significantly enhanced, accompanied by minimized water layer formation. The optimal PPy nanofibers-based K + sensor achieved a high sensitivity of 62 mV decade -1 , good selectivity, and solid stability. After being integrated with a temperature sensor, the manufactured wearable sensor realized accurate monitoring of K + fluctuation in the human sweat., (© 2024 Wiley‐VCH GmbH.)

With the increasing demands for novel flexible organic electronic devices, conductive polymers are now becoming the rising star for reaching such targets, which has witnessed significant breakthroughs in the fields of thermoelectric devices, solar cells, sensors, and hydrogels during the past decade due to their outstanding conductivity, solution-processing ability, as well as tailorability. However, the commercialization of those devices still lags markedly behind the corresponding research advances, arising from the not high enough performance and limited manufacturing techniques. The conductivity and micro/nano-structure of conductive polymer films are two critical factors for achieving high-performance microdevices. In this review, the state-of-the-art technologies for developing organic devices by using conductive polymers are comprehensively summarized, which will begin with a description of the commonly used synthesis methods and mechanisms for conductive polymers. Next, the current techniques for the fabrication of conductive polymer films will be proffered and discussed. Subsequently, approaches for tailoring the nanostructures and microstructures of conductive polymer films are summarized and discussed. Then, the applications of micro/nano-fabricated conductive films-based devices in various fields are given and the role of the micro/nano-structures on the device performances is highlighted. Finally, the perspectives on future directions in this exciting field are presented., (© 2023 Wiley-VCH GmbH.)

Functional membranes generally wear out when applying in harsh conditions such as a strong acidic environment. In this work, high acid-resistance, long-lasting, and low-cost functional membranes are prepared from engineered hydrogen-bonding and pH-responsive supramolecular nanoparticle materials. As a proof of concept, the prepared membranes for dehydration of alcohols are utilized. The synthesized membranes have achieved a separation factor of 3000 when changing the feed solution pH from 7 to 1. No previous reports have demonstrated such unprecedentedly high-record separation performance (pervaporation separation index is around 1.1 × 10 7  g m -2  h -1 ). More importantly, the engineered smart membrane possesses fast self-repairing ability (48 h) that is inherited from the dynamic hydrogen bonds between the hydroxyl groups of polyacrylic acid and carbonyl groups of polyvinylpyrrolidone. To this end, the designed supramolecular materials offer the membrane community a new material type for preparing high acid resistance and long-lasting membranes for harsh environmental cleaning applications., (© 2021 The Authors. Advanced Science published by Wiley-VCH GmbH.)

The robustness of carbon nanomaterials and their potential for ultrahigh permeability has drawn substantial interest for separation processes. However, graphene oxide membranes (GOms) have demonstrated limited viability due to instabilities in their microstructure that lead to failure under cross-flow conditions and applied hydraulic pressure. Here we present a highly stable and ultrapermeable zeolitic imidazolate framework-8 (ZIF-8)-nanocrystal-hybridized GOm that is prepared by ice templating and subsequent in situ crystallization of ZIF-8 at the nanosheet edges. The selective growth of ZIF-8 in the microporous defects enlarges the interlayer spacings while also imparting mechanical integrity to the laminate framework, thus producing a stable microstructure capable of maintaining a water permeability of 60 l m -2  h -1  bar -1 (30-fold higher than GOm) for 180 h. Furthermore, the mitigation of microporous defects via ZIF-8 growth increased the permselectivity of methyl blue molecules sixfold. Low-field nuclear magnetic resonance was employed to characterize the porous structure of our membranes and confirm the tailored growth of ZIF-8. Our technique for tuning the membrane microstructure opens opportunities for developing next-generation nanofiltration membranes.

Water transport rate in network membranes is inversely correlated to thickness, thus superior permeance is achievable with ultrathin membranes prepared by complicated methods circumventing nanofilm weakness and defects. Conferring ultrahigh permeance to easily prepared thicker membranes remains challenging. Here, a tetrakis(hydroxymethyl) phosphonium chloride (THPC) monomer is discovered that enables straightforward modification of polyamide composite membranes. Water permeance of the modified membrane is ≈6 times improved, give rising to permeability (permeance × thickness) one magnitude higher than state-of-the-art polymer nanofiltration membranes. Meanwhile, the membrane exhibits good rejection (R Na2SO4 = 98%) and antibacterial properties under crossflow conditions. THPC modification not only improves membrane hydrophilicity, but also creates additional angstrom-scale channels in polyamide membranes for unimpeded transport of water. This unique mechanism provides a paradigm shift in facile preparation of ultrapermeable membranes with unreduced thickness for clean water and desalination., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The separation efficiency of photogenerated electrons and holes is the key to photocatalytic performance. Layered BiOCl is a kind of newly exploited efficient photocatalyst, but its wide-spread practical application is hindered by the rapid recombination of photogenerated electron-hole pairs and low quantum efficiency. In this study, we prepared a composite photocatalyst via a hydrothermal method in which (NH 4 ) 3 PW 12 O 40 (NH 4 PTA) is the acceptor of photoelectrons from BiOCl. The photocatalytic performance of variants of BiOCl-NH 4 PTA was evaluated by the removal efficiency of methyl orange (MO). The experimental results showed that the BiOCl-NH 4 PTA[ n (Bi): n (W)=1:1] had the best photocatalytic activity under the irradiation of sunlight simulated by xenon light. The photocatalytic mechanism was investigated using the reactive species trapping experiments. It was found that MO could be photodegraded by,·OH, and holes over BiOCl. Differently, and·OH were the dominant reactive species for the reactions over the composite photocatalyst. It was proved that NH 4 PTA was the acceptor of photoelectrons by the XPS on the photocatalyst before and after reaction. The photocurrent test verified the superior photocatalysis of BiOCl-NH 4 PTA which was attributed to the efficient separation of electron-hole pairs.

TiO 2 is a promising photocatalysis for degradation of organic pollutants due to its innocuity. However, its widespread practical application was hindered by the fast combination speed of photogenerated electron-hole pairs and low quantum efficiency. In this study, we prepared ZnTiO 3 -TiO 2 using the Sol-Gel method to get heterojunctions, which exhibit efficient separation of photogenerated electron-hole pairs. The photocatalytic performances of various ZnTiO 3 -TiO 2 were evaluated by the removal efficiency of Methyl orange. The experimental results showed that the ZnTiO 3 -TiO 2 (ZnTiO 3 :TiO 2 =0.3), which was calcinated under 600℃, had the best photocatalytic activity under ultraviolet light. The photocatalyst was stable under a wide range of pH (2.5-12.5). The photocurrent and ESR analysis verified the superior photocatalysis of ZnTiO 3 -TiO 2 , which was attributed to the efficient separation of electron-hole pairs induced by the heterojunctions.

Breast cancers (BC) are treated with surgery, radiotherapy, and chemotherapy. Neoadjuvant chemotherapy (NACT) is an emerging treatment option in many cancers and is given before primary therapy to shrink tumor size. The efficacy of NACT in varied settings of BC, such as inoperable tumors, borderline resectable tumors, and breast-conserving surgery, has been debated extensively in literature, and the results remain unclear and depended on a wide variety of factors such as cancer type, disease extent, and the specific combination of chemotherapy drugs. This study was performed to examine the efficacy, toxicity, and tolerability of pirarubicin (THP) and epirubicin (EPI) in combination with docetaxel and cyclophosphamide in a NACT setting for BC. A total of 48 patients with stage II or III breast cancers were randomly divided into two groups: THP group and EPI group. The patients in THP group received 2-4 cycles of neoadjuvant chemotherapy with DTC regimen (docetaxel, THP, cyclophosphamide), while patients in the EPI group received 2-4 cycles of DEC regimen (docetaxel, EPI, cyclophosphamide) before surgery. The incidence of adverse reactions and the efficacy of the treatment regimen were compared between the two groups. Prognostic evaluation indexes were estimated by Kaplan-Meier survival analysis, including the 5-year disease-free survival (DFS) and overall survival (OS). The overall response rate in THP group was 83.3 %, and the EPI group showed a response rate of 79.2 %, with no statistically significant difference in response rate between the two groups. The incidence of cardiac toxicity, myelosuppression, nausea, and vomiting in the THP group was significantly lower than the EPI group (all P < 0.05). The incidence of hepatic toxicity, alopecia, and diarrhea in the THP group was also lower than the EPI group, but these differences were not statistically significant. The 5-year DFS and OS in THP versus EPI groups were 80 versus 76 % (DFS) and 86 versus 81 % (OS), respectively. Our study found that NACT with DTC regimen and DEC regimen were both very effective in treatment of BC. However, THP-based combination therapy was associated with significantly lower incidence of cardiac toxicity, myelosuppression, nausea, and vomiting.

Cadherin-1 (CHD1), as an invasion suppressor gene, could suppress tumor cell invasion and metastasis in various tumors, but reduced CHD1 levels, resulting from epigenetic silencing, are common in poorly differentiated, advanced stage carcinomas. This meta-analysis was performed to evaluate the relationships between promoter methylation of CHD1 and breast cancer. Relevant studies were retrieved from the Web of Science (1945 ~ 2013), the Cochrane Library (Issue 12, 2013), PubMed (1966 ~ 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), and the Chinese Biomedical Database (CBM) (1982 ~ 2013) using a systematic literature search. Results were summarized by meta-analyses, conducted using the STATA software (version 12.0, Stata Corporation, College Station, TX, USA). Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were calculated. In the present meta-analysis, 9 cohort studies with a total of 425 patients with breast cancer were included. Our meta-analysis results demonstrated that the frequency of CHD1 promoter methylation in cancer tissues was significantly higher than that in normal tissues, adjacent tissues, and benign tissues (cancer tissue vs. normal tissue OR = 30.87, 95 % CI = 16.76 ~ 56.86, P < 0.001; cancer tissue vs. adjacent tissue OR = 23.30, 95 % CI = 12.85 ~ 42.26, P < 0.001; cancer tissue vs. benign tissue OR = 2.94, 95 % CI = 1.60 ~ 5.40, P < 0.001; respectively). Ethnicity-stratified analysis indicated that aberrant CHD1 promoter methylation was strongly correlated with breast cancer among both Asians and Caucasians in the majority of subgroups. Our results suggest that aberrant promoter methylation of the CHD1 gene may have a high frequency in breast cancer tissues. Thus, CHD1 methylation could be correlated with the pathogenesis of breast cancer.

Background: Gadolinium chloride (GdCl(3)) is a specific inhibitor of Kupffer cells (KCs), which are important promoters of various liver injuries. It is therefore of interest to explore the role of KCs in liver ischemia-reperfusion injury and their relations with apoptosis caused by ischemia-reperfusion injury., Methods: One hundred male Wistar rats (190-210 g, 6-7 weeks old) were divided into two groups at random, GdCl(3) group and control group. Samples were collected at 0.5, 1, 6, 12, and 24 hours from each group after reperfusion. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured by an automatic biochemical analyzer. TNF-alpha in serum was measured by enzyme-linked immunosorbent assay (ELISA). Malondialdehyde (MDA) in the liver mitochondria was measured by a colorimetric method. Pathological changes in the liver and immunohistochemical staining for caspase-3 were observed under an optical microscope. The ratio of apoptotic cells was measured by TdT-mediated dUTP nick-end labeling (TUNEL), and ultrastructural features of apoptosis were observed with a transmission electron microscope (TEM)., Results: The levels of ALT in the GdCl(3) group were lower than those in the control group after reperfusion for 0.5, 1, 6 and 12 hours (P<0.05); and the levels of AST in the GdCl(3) group were lower than those in the control group after reperfusion for 6 and 12 hours (P<0.05). The levels of TNF-alpha in the GdCl(3) group were lower than those in the control group after reperfusion for each time (P<0.05). The concentrations of MDA after reperfusion in the GdCl(3) group were lower than those in the control group after reperfusion for 6, 12 and 24 hours (P<0.05). After reperfusion for 0.5, 1, 6 and 12 hours, the integral optical density (IOD) of caspase-3-positive cells was lower in the GdCl(3) group than in the control group (P<0.05). After reperfusion for 1, 6, and 12 hours, the IOD of cells stained by TUNEL in the GdCl(3) group was lower than that in the control group (P<0.05)., Conclusions: GdCl(3) inhibits the activity of ALT, AST and TNF-alpha, decreases the accumulation of MDA in mitochondria, and depresses the expression of caspase-3 in liver after ischemia-reperfusion. This may be an important protective mechanism by depressing KCs and indirectly inhibiting liver cell apoptosis.

Background: Survivin is a new and important gene in the regulation of apoptosis. It is very important to explore the effect of the expression of survivin protein caused by ischemia-reperfusion (IR) injury. The effect of IR injury caused by ischemic preconditioning (IP) on the liver in rats and the relation between the protective effect of IP and the expression of survivin are unclear., Methods: One hundred and fifty male Wistar rats (weighing 190-210 g, aged 6-7 weeks) were divided into three groups at random: ischemic preconditioning (IP), ischemia-reperfusion (IR) and sham-operation (SO). Sample specimens were collected from each group at 6, 12, 24, 48, and 72 hours after reperfusion. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured by an automatic biochemical analyzer. Malondialdehyde (MDA) in liver tissue was measured. Pathological changes in the liver and immunohistochemical staining for survivin were determined with an optical microscope., Results: The ALT levels in the IP and IR groups after reperfusion at each time were higher than those in the SO group (P<0.05), whereas after reperfusion for 6 and 12 hours, the ALT levels in the IP group were lower than those in the IR group (P<0.05). The AST levels in all IP and IR groups were higher than those in the SO group (P<0.05), whereas after reperfusion for 12, 24, 48 and 72 hours, the AST levels in the IP group were lower than those in the IR group (P<0.05). The MDA concentrations after reperfusion in the IP group were lower than those in the IR group (P<0.05), though the MDA concentrations in the IP and IR groups increased in contrast to those in the SO group after reperfusion at each time (P<0.05). After reperfusion for 12, 24, 48 and 72 hours, the number of survivin-positive cells was larger in the IP and IR groups than in the SO group (P<0.05). After reperfusion for 12, 24, and 48 hours the number of survivin-positive cells in the IP group increased compared with that in the IR group (P<0.05)., Conclusions: IR increases the protein expression of survivin in liver tissue. IP inhibits the accumulation of MDA, advances the expressive phase of survivin protein in hepatic tissue, and improves liver function.

Background: Melatonin exerts complex physiological and pharmacological effects on multiple systems and organs. We hypothesized that melatonin might abate ischemia/reperfusion (I/R) injury in the liver by inhibiting excessive oxidative stress and keeping nitric oxide (NO) from being scavenged by free radicals. The aim of the present study was to investigate whether melatonin protects the liver from I/R injury and, if so, by what underlying mechanism., Methods: Under anesthesia, Wistar rats were intraperitoneally injected with 20 mg/kg melatonin (dissolved in physiological saline containing 4% ethanol, Mel group), 4% alcohol (Alc group), or physiological saline (NS group). The artery, portal vein and bile duct of the left lobe of the liver were clamped for 60 minutes and then released. At different time points after I/R, the rats were sacrificed and blood samples were collected to measure the levels of serum alanine aminotransferase (ALT), lactic dehydrogenase (LDH), and NO. Hepatic tissue samples were collected for measuring endothelin expression by immunohistochemical staining and for routine morphological and histological examination., Results: The levels of both ALT and LDH in the Mel group were significantly reduced for up to 24 hours after I/R compared with the Alc and NS groups (P<0.05). The levels of NO in the Mel group were significantly elevated for up to 12 hours after I/R relative to the NS group (P<0.05). The NO levels were also elevated at 0.5 and 6 hours after I/R in the Alc group (P<0.05). The immunohistochemical staining of hepatic tissue showed that endothelin-positive cells were significantly fewer in the Mel group than in the Alc and NS groups at 6 hours after I/R (P<0.01). The necrosis of hepatocytes and the destruction of hepatic cords in the Alc and NS groups were greatly improved in Mel-treated rats, which is in concert with our functional data., Conclusions: Pretreatment with melatonin increased NO bioavailability and decreased endothelin expression, and consequently played a protective role in preserving both liver function and structure during ischemia and reperfusion injury.