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Background: Postoperative pancreatic fistula (POPF) is the most prevalent complications following minimally invasive pancreaticoduodenectomy (MIPD). Only one model related to MIPD exists, and previous POPF scoring prediction methods are based on open pancreaticoduodenectomy patients. Our objectives are to determine the variables that may increase the probability of pancreatic fistula following MIPD and to develop and validate a POPF predictive risk model. Methods: Data from 432 patients who underwent MIPD between July 2015 and May 2022 were retrospectively collected. A nomogram prediction model was created using multivariate logistic regression analysis to evaluate independent factors for POPF in patients undergoing MIPD in the modeling cohort. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) and the calibration curve were used to verify the nomogram prediction model internally and externally within the modeling cohort and the verification cohort. Results: Multivariate logistic regression analysis showed that body mass index (BMI), albumin, triglycerides, pancreatic duct diameter, pathological diagnosis and intraoperative bleeding were independent variables for POPF. On the basis of this information, a model for the prediction of risks associated with POPF was developed. In accordance with the ROC analysis, the modeling cohort's AUC was 0.819 (95% CI 0.747–0.891), the internal validation cohort's AUC was 0.830 (95% CI 0.747–0.912), and the external validation cohort's AUC was 0.793 (95% CI 0.671–0.915). Based on the calibration curve, the estimated values of POPF have a high degree of concordance with the actual values that were measured. Conclusions: This model for predicting the probability of pancreatic fistula following MIPD has strong predictive capacity and can provide a trustworthy predictive method for the early screening of high-risk patients with pancreatic fistula after MIPD and timely clinical intervention. [ABSTRACT FROM AUTHOR]

Acid mine drainage is highly acidic and contains heavy metals, which can be harmful to soil, water, plants, and animals. To solve this issue, surface passivation could effectively prevent acid mine drainage at the source. However, traditional silane passivators lack long-term stability and require high-temperature conditions for the passivation of pyrite. Here, we prepared a self-healing passivator at room temperature. The passivation ability and self-healing performance of the passivator were investigated by release experiments, chemical leaching experiments, electrochemical experiments, and various characterization methods. Result shows that the passivation efficiency still reaches 68.4% for iron and 68.8% for sulfate after 60 days of leaching experiments. We observed that scratches on the surface of the passivator-coated pyrite gradually diminish due to its self-healing ability. [ABSTRACT FROM AUTHOR]

This paper presents a new method for accurately measuring the vocabulary size of second language (L2) learners. Traditional vocabulary size tests (VSTs) are limited in capturing a tester's vocabulary and are often population-specific. To overcome these issues, we propose an intelligent vocabulary size measurement method that utilizes massive robot testers. They are equipped with randomized and word-frequency-based vocabularies to simulate L2 learners' variant vocabularies. An intelligent vocabulary size test (IVST) is developed to precisely measure vocabulary size for any population. The robot testers "take" the IVST, which dynamically generates quizzes with varying levels of difficulty adapted to the estimated tester's vocabulary size in real-time using an artificial neural network (ANN) through iterative learning. The effectiveness of the IVST is factually verified by their visible vocabularies. Additionally, we apply a long short-term memory (LSTM) model to further enhance the method's performance. The proposed method has demonstrated high reliability and effectiveness, achieving accuracies of 98.47% for the IVST and 99.87% for the IVST with LSTM. This novel approach provides a more precise and reliable method for measuring vocabulary size in L2 learners compared to traditional VSTs, offering potential benefits to language learners and educators. [ABSTRACT FROM AUTHOR]

The issue of hearing protection in the presence of noise pollution is of great importance in the fields of environmental science and clinical medicine. Currently, the clinical significance of Klotho in relation to hearing has not been revealed. The aim of this study was to examine the correlation between serum Klotho levels and Pure Tone Average (PTA) hearing thresholds among individuals in the U.S.. The analysis involved a sample of 1,781 individuals aged 20 to 69, obtained from the 2007–2012 National Health and Nutrition Examination Survey. Various methods were utilized for the analysis, including univariate and multivariate linear regression, stratified analysis, smooth curve fitting, a two-segment linear regression model, and log-likelihood ratio analysis. The results of the univariate analysis indicated that serum Klotho concentration, age, education level, hypertension, diabetes, and smoking all exhibited a significant influence on PTAs. After adjusting for potential confounding factors, it was observed that a decrease in serum Klotho was significantly associated with PTA thresholds at low frequency (β = -0.002; 95% CI: -0.003, -0.001; P = 0.004), speech frequency (β = -0.002; 95% CI: -0.003, -0.001; P = 0.007), and high frequency (β = -0.002; 95% CI: -0.003, -0.001; P = 0.045). Specifically, for every 1 pg/ml decrease in serum Klotho concentration, the PTAs increased by 0.002 dB. Moreover, age and gender-specific analyses revealed significant associations. For individuals aged 59–69, a significant association was found between serum Klotho concentration and high-frequency PTA (β = -4.153; 95% CI: -7.948, -0.358; P = 0.032). Additionally, among females, significant associations were observed between serum Klotho concentration and speech-frequency PTA (β = -1.648, 95% CI: -3.197, -0.099; P = 0.037) as well as high-frequency PTA (β = -3.046; 95% CI: -5.319, -0.772; P = 0.009). Finally, the results of smooth curve fitting and threshold effect analyses indicated a potential negative linear correlation between serum Klotho concentration and PTA thresholds. In conclusion, a lower level of serum Klotho was found to be associated with increased hearing thresholds, particularly among the elderly population. This finding has significant implications for the prevention and treatment of hearing damage. [ABSTRACT FROM AUTHOR]

Nucleotide excision repair removes DNA lesions caused by ultraviolet light, cisplatin-like compounds and bulky adducts1. After initial recognition by XPC in global genome repair or a stalled RNA polymerase in transcription-coupled repair, damaged DNA is transferred to the seven-subunit TFIIH core complex (Core7) for verification and dual incisions by the XPF and XPG nucleases2. Structures capturing lesion recognition by the yeast XPC homologue Rad4 and TFIIH in transcription initiation or DNA repair have been separately reported3–7. How two different lesion recognition pathways converge and how the XPB and XPD helicases of Core7 move the DNA lesion for verification are unclear. Here we report on structures revealing DNA lesion recognition by human XPC and DNA lesion hand-off from XPC to Core7 and XPA. XPA, which binds between XPB and XPD, kinks the DNA duplex and shifts XPC and the DNA lesion by nearly a helical turn relative to Core7. The DNA lesion is thus positioned outside of Core7, as would occur with RNA polymerase. XPB and XPD, which track the lesion-containing strand but translocate DNA in opposite directions, push and pull the lesion-containing strand into XPD for verification.Cryo-electron microscopy structures reveal how XPC recognizes DNA lesions and recruits XPA and the TFIIH core complex for lesion verification in nucleotide excision repair. [ABSTRACT FROM AUTHOR]

Purpose: This study was designed to assess the computed tomography maximum (CTmax) value on pretherapeutic arterial phase computed tomography (APCT) images to predict pancreatic neuroendocrine tumours (pNETs) recurrence and clarify its role in predicting the outcome of tumour therapy. Methods: This retrospective study enrolled 250 surgical patients and 24 nonsurgical patients with sunitinib-based treatment in our hospital from 2008 to 2019. CT images were assessed, the maximum value was defined as "CTmax," and recurrence-free survival (RFS) or progression-free survival (PFS) was compared between a high-CTmax group and a low-CTmax group among patients who underwent surgical resection or nonsurgical, sunitinib-based treatment according to the CTmax cutoff value. Results: In ROC curve analysis, a CTmax of 108 Hounsfield units, as the cutoff value, achieved an AUC of 0.796 in predicting recurrence. Compared with the low-CTmax group, the high-CTmax group had a longer RFS (p < 0.001). Low CTmax was identified as an independent factor for RFS (p < 0.001) in multivariate analysis; these results were confirmed using the internal validation set. The CTmax value was significantly correlated with the microvascular density (MVD) value (p < 0.001) and the vascular endothelial growth factor receptor 2 (VEGFR2) score (p < 0.001). Furthermore, the high-CTmax group had a better PFS than the low-CTmax group among the sunitinib treatment group (p = 0.007). Conclusions: The tumour CTmax on APCT might be a potential and independent indicator for predicting recurrence in patients who have undergone surgical resection and assessing the efficacy of sunitinib for patients with advanced metastatic pNETs. [ABSTRACT FROM AUTHOR]

The edge S sites of thermodynamically stable 2H MoS2 are active for hydrogen evolution reaction (HER) but the active sites are scarce. Despite the dominance of the basal S sites, they are generally inert to HER because of the low p-band center. Herein, we reported a synergistic combination of phase engineering and NH4+ intercalation to promote the HER performance of MoS2. The rational combination of 1T and 2H phases raises the p-band center of the basal S sites while the intercalated NH4+ ions further optimize and stabilize the electronic band of these sites. The S sites with regulated band structures afford moderate hydrogen adsorption, thus contributing to excellent HER performance over a wide pH range. In an acid medium, this catalyst exhibits a low overpotential of 169 mV at 10 mA·cm−2 and Tafel slope of 39 mV·dec−1 with robust stability, superior to most of recently reported MoS2-based non-noble catalysts. The combined use of in/ex-situ characterizations ravels that the appearance of more unpaired electrons at the Mo 4d-orbital reduces the d-band center which upshifts the p-band center of the adjacent S for essentially improved HER performance. This work provides guidelines for the future development of layered transition-metal-dichalcogenide catalysts. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to compare the short- and long-term outcomes of laparoscopic surgery (LS) and open surgery (OP) for perihilar cholangiocarcinoma (PHC) using a large real-world dataset in China. Methods: Data of patients with PHC who underwent LS and OP from January 2013 to October 2018, across 10 centers in China, were extracted from medical records. A comparative analysis was performed before and after propensity score matching (PSM) in the LS and OP groups and within the study subgroups. The Cox proportional hazards mixed-effects model was applied to estimate the risk factors for mortality, with center and year of operation as random effects. Results: A total of 467 patients with PHC were included, of whom 161 underwent LS and 306 underwent OP. Postoperative morbidity, such as hemorrhage, biliary fistula, abdominal abscess, and hepatic insufficiency, was similar between the LS and OP groups. The median overall survival (OS) was longer in the LS group than in the OP group (NA vs. 22 months; hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.02–1.39, p = 0.024). Among the matched datasets, OS was comparable between the LS and OP groups (NA vs. 35 months; HR 0.99, 95% CI 0.77–1.26, p = 0.915). The mixed-effect model identified that the surgical method was not associated with long-term outcomes and that LS and OP provided similar oncological outcomes. Conclusions: Considering the comparable long-term prognosis and short-term outcomes of LS and OP, LS could be a technically feasible surgical method for PHC patients with all Bismuth–Corlett types of PHC. [ABSTRACT FROM AUTHOR]

Pancreatic adenocarcinoma (PAAD) is the third leading cause of cancer-related deaths, with a 5-year relative survival rate of 6%. Hence, novel therapeutic targets need to be urgently explored for PAAD. Recently, oxidative phosphorylation (OXPHOS) has been identified to contribute to the development of PAAD. Nicotinamide adenine dinucleotide + hydrogen (NADH) dehydrogenase (ubiquinone) 1 alpha subcomplex 4 (NDUFA4) is known to affect the mitochondrial respiration pathway. However, the function of NDUFA4 in PAAD remains unclear. In this study, NDUFA4 expression was examined in samples from patients with PAAD using real-time polymerase chain reaction and immunohistochemical staining. Furthermore, cell proliferation and cell cycle were analyzed using Cell Counting Kit-8 assay and flow cytometry. A xenograft tumor model derived from a PAAD cell line was developed to validate the in vitro findings. NDUFA4 was observed to be upregulated in the PAAD samples, and high levels were associated with a poor survival rate. NDUFA4 knockdown reduced cell proliferation by inducing G1 arrest in SW1990 cells. Mechanistically, NDUFA4 knockdown decreased the oxygen consumption rate, cellular adenosine triphosphate level, mitochondrial complex IV activity, and protein levels of COX6C and COX5B, which indicated the suppression of OXPHOS. In contrast, NDUFA4 overexpression exerted the opposite effects. Finally, NDUFA4 knockdown significantly inhibited the growth of the xenograft tumor derived from the SW1990 cell line in vivo. Therefore, NDUFA4 contributes to PAAD proliferation by enhancing OXPHOS. [ABSTRACT FROM AUTHOR]

The mechanisms of neuroendocrine tumor (NET) were still poorly understood, largely due to the lack of preclinical models of neuroendocrine neoplasms. Herein, we established and characterized SPNE1 cell lines from primary pancreatic NET tissue obtained from a 44-year-old female. Neuroendocrine character of SPNE1 was compared with existing non-functional cell lines BON1 and QGP1, and the results indicated expressions of multiple NET-specific markers in SPNE1 were higher relative to BON1 and QGP1. The growth character measured by Ki67 labeling index, cell cycle analysis, and 3D matrigel spheroid essay indicated that the proliferative rate of SPNE1 was lower than that of BON1 and QGP1. SPNE1 also was characterized with cancer stemness because of the higher proportion of CD44 + and CD117 + subpopulations relative to BON1, whereas it was similar to that of QGP1. Interestingly, SPNE1 highly expressed somatostatin receptors (SSTR2 and SSTR5) and angiogenic factors (VEGF1). SPNE1 had sensitive response to the four clinical treatments including tyrosine kinase inhibitor (TKI), mTOR inhibitors, somatostatin analogs (SSA), chemotherapy, which was similar to the BON1 and QGP1. Subcutaneous transplantations of SPNE1 also present the tumorigenicity, and neuroendocrine marker expression of xenograft tumors resembled the original human NET tissue. Then, we found a total of 8 common mutation in BON1, QGP1 and SPNE1 included CROCC, FAM135A, GPATCH4, CTBP2, FBXL14, HERC2, HYDIN, and PABPC3 using whole-exome sequencing (WES), and more neuroendocrine-related functional processes were enriched based on the private mutation genes in SPNE1, such as neuron migration, insulin secretion, and neuron to neuron synapse. In brief, SPNE1 could be used as a relevant model to study pancreatic NET biology and to develop novel treatment options. [ABSTRACT FROM AUTHOR]

Oil and gas pipeline leakages lead to not only enormous economic loss but also environmental disasters. How to detect the pipeline damages including leakages and cracks has attracted much research attention. One of the promising leakage detection method is to use lead zirconate titanate (PZT) transducers to detect the negative pressure wave when leakage occurs. PZT transducers can generate and detect guided waves for crack detection also. However, the negative pressure waves or guided stress waves may not be easily detected with environmental interference, e.g., the oil and gas pipelines in an offshore environment. In this paper, a Gaussian mixture model-hidden Markov model (GMM-HMM) method is proposed to process PZT transducers' outputs for detecting the pipeline leakage and crack depth in changing environment and time-varying operational conditions. Leakages in different sections or crack depths are considered as different states in hidden Markov models (HMMs). One time-domain damage index and one frequency domain damage index are extracted from signals collected from PZT transducers, then extracted indices are formed as observation emissions in the HMM. The observation probability distribution matrix in HMM is initialized by a Gaussian mixture model (GMM) to address signal uncertainties. After the HMM parameter initialization, an iterative training process through the Baum–Welch algorithm is applied to get the optimized parameters of the GMM-HMM. Leakage location or crack depth is decided by the maximum posterior probability from the trained model. Two different experimental settings and results show that the GMM-HMM method can recognize the crack depth and leakage of pipeline such as whether there is a leakage, where the leakage is. [ABSTRACT FROM AUTHOR]

The present study aimed to explore the effect of a range of moisture content levels, including 65%, 72%, and 78%, on physicochemical properties and microfauna communities during vermicomposting of municipal sludge. As a result, death of perishable microfauna together with the degradation of organic matter was the dominant response in all groups in the early period of vermicomposting, while the effects of moisture content levels on various physiochemical parameters did not appear until the mid-later period. After the treatment with 78% moisture content, the content of mineral nitrogen was 1.186 g/kg in the sludge, with a 9.36 × 103 ind./g of microfauna quantity and 663.01 g of earthworm biomass. The values of these three measurements in 78% group were significantly higher than other two groups (p < 0.05), indicating that the effects of 78% moisture content were more pronounced for promoting nitrogen mineralization as well as microfauna and earthworms growth during vermicomposting. Specifically, testate amoebae were strongly associated with nitrification process, while nematodes were related to ammonification and phosphorus mineralization, of which testate amoebae had great potential of being bioindicators during vermicomposting of municipal sludge. [ABSTRACT FROM AUTHOR]

Pancreaticoduodenectomy (PD) is one of the most complex and delicate operations in abdominal surgery. With the development of laparoscopic techniques, more and more pancreatic experts have become skilled in laparoscopic pancreaticoduodenectomy (LPD). However, the short-term efficacy of LPD compared to open pancreaticoduodenectomy (OPD) remains unclear. Here, we performed a propensity score matching study aiming to compare the short outcomes of patients who underwent LPD or OPD after the learning curve and established a risk model of pancreatic fistula. The data of 346 patients who had OPD or LPD from July 2015 to January 2020 were retrieved. After a 1:1 matching, 224 patients remained. The operation time was significantly longer (P = 0.001) but the amount of bleeding was significantly lower (P = 0.001) in the LPD group than in the OPD group. Patients in LPD group had fewer blood transfusions (P = 0.002) than those in OPD group. More lymph nodes (P < 0.001) were dissected in LPD group. The rate of grade B/C pancreatic fistula was significantly higher in the LPD group than in the OPD group (16.1% vs. 6.3%, P = 0.002). By multi variate Logistic regression analysis, we identified pancreatic tumor, malignancy and low body mass index were risk factors of Grade B/C pancreatic fistula after PD operation. Then, we developed a Grade B/C pancreatic fistula nomogram with the risk factors. The C-index of the nomogram was 0.836 (95% CI 0.762–0.910). In conclusion, LPD could be technically feasible, get less trauma and achieve similar short-term outcome as compared with OPD. [ABSTRACT FROM AUTHOR]

A magnetically separable photocatalytic g-C3N4/NiFe2O4 nanocomposite was obtained via a two-step method. In the first step, the magnetic NiFe2O4 nanoparticles were acquired in a few minutes by ionic liquid self-combustion approach which significantly reduced the synthesis time of nanocomposites. Besides, the research of g-C3N4/NiFe2O4 nanocomposites for the visible-light-driven degradation of methylene blue in the absence of H2O2 was detailed. Compared with pure g-C3N4 and NiFe2O4, the as-prepared nanocomposites with NiFe2O4 doping of 12% manifested the enhanced photocatalytic activity and stability after three cycles for degrading methylene blue, and the photocatalytic process followed first-order reaction kinetics. Trapping experiments demonstrated that the H+ and OH• scavengers are the main active species and O2•− has a small effect for visible-light-driven degradation of methylene blue. [ABSTRACT FROM AUTHOR]

The purpose of the study is to evaluate whether laparoscopic pancreatoduodenectomy (LPD) is safe and feasible for elderly patients. From December 2015 to January 2019, 142 LPD surgeries and 93 OPD surgeries were performed by the same surgeon in the third affiliated hospital of Soochow University. After applying the inclusion and exclusion criteria, we retrospectively collected the date of three defined groups: LPD aged < 70 years (group I, 84 patients), LPD aged ≥ 70 years (group II, 56 patients) and OPD aged ≥ 70 years (group III, 28 patients). Baseline characteristics and short-term surgical outcomes of group I and group II, group II and group III were compared. Totally, 168 patients were included in this study; 100 cases were men; 68 cases were women; mean age was 67.9 ± 9.5 years. LPD does not perform as well in elderly as it does in non-elderly patients in terms of intraoperative blood loss (300.0 (200.0–500.0) ml vs. 200.0 (100.0–300.0) ml, p = 0.003), proportion of intraoperative transfusion (17.9% vs. 6.0%, p = 0.026) and time to oral intake (5.0 (4.0–7.0) day vs. 5.0 (3.0–6.0) day, p = 0.036). Operative time, conversion rate, postoperative stay, and proportion of reoperation, Clavien–Dindo classification, 30-day readmission and 90-day mortality were similar in two groups. In elderly patients, when compared with OPD, LPD had the advantage of shorter time to start oral intake (5.0 (4.0–7.0) day vs. 7.0 (5.0–11.3) day, p = 0.005) but the disadvantage of longer operative time (380.0 (306.3–447.5) min vs. 292.5 (255.0–342.5) min, p < 0.001) and higher hospitalization cost (12447.3 (10,189.7–15,340.0) euros vs. 7251.9 (8994.0–11,717.4) euros, p < 0.001). There was no difference between the two groups in terms of postoperative stay, and proportion of reoperation, Clavien–Dindo classification, 30-day readmission and 90-day mortality. LPD is safe and feasible for elderly people, but we need to consider its high cost and long operative time over OPD. [ABSTRACT FROM AUTHOR]

This study aimed to promote vermicomposting performance for recycling fresh fruit and vegetable wastes (FVWs) and to assess microbial population and community of final products. Five fresh FVWs including banana peels, cabbage, lettuce, potato, and watermelon peels were chosen as earthworms' food. The fate test of earthworms showed that 30 g fresh FVWs/day was the optimal loading and the banana peels was harmful for the survival of Eisenia fetida. The followed vermicomposting test revealed lower contents of total carbon and weaker microbial activity in final vermicomposts, relative to those in compared systems without earthworms worked. The leachate from FVWs carried away great amounts of nutrients from reactors. Additionally, different fresh FVWs displayed dissimilar stabilization process. Molecular biological approaches revealed that earthworms could broaden bacterial diversity in their products, with significant greater populations of actinobacteria and ammonia oxidizing bacteria than in control. This study evidences that vermicomposting efficiency differs with the types and loadings of fresh FVWs and vermicomposts are rich in agricultural probiotics. [ABSTRACT FROM AUTHOR]

In this study, the effect of earthworms on microbial features during vermicomposting of pelletized dewatered sludge (PDS) was investigated through comparing two degradation systems with and without earthworm E isenia fetida involvement. After 60 days of experimentation, a relatively stable product with low organic matter and high nitrate and phosphorous was harvested when the earthworms were involved. During the process, earthworms could enhance microbial activity and biomass at the initial stage and thus accelerating the rapid decomposition of PDS. The end products of vermicomposting allowed the lower values of bacterial and eukaryotic densities comparison with those of no earthworm addition. In addition, the presence of earthworms modified the bacterial and fungal diversity, making the disappearances of some pathogens and specific decomposing bacteria of recalcitrant substrates in the vermicomposting process. This study evidences that earthworms can facilitate the stabilization of PDS through modifying microbial activity and number and community during vermicomposting. [ABSTRACT FROM AUTHOR]

Background: The role of costimulatory molecules expressed on lymphocytes and thyrocytes in hyperthyroidism has attracted increasing attention and research has shown a close correlation between variant expression of these molecules on lymphocytes and thyrocytes and the development of GD. Meterials and Methods: Thyroid tissues were collected from GD patients during surgery and from Hashimoto disease (HT) and non-toxic goiter (NTG) patients as controls. ICOSL expression on infiltrated B cells and TFC was detected by flow cytometry (FCM), reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC). Variation in ICOSL expression on TFC in primary cultures was analyzed in the absence or presence of cytokines using FCM assays. The role of ICOS-ICOSL signaling in proliferation, thyroid hormone production and thyroglobulin (Tg) release was investigated in primary TFC cultures using ICOS gene transfected L929 cells (ICOS-L929 cells) and the blocking ICOSL antibody (11 C4) in MTT assays and radioimmunoassays. Results and Discussion: ICOSL expression on infiltrated B cells and TFC was detected in GD patient tissue. However, ICOSL expression was only detected on infiltrated B cells in control HT and NTG patient tissue. ICOSL expression on TFC was induced in vitro by the proinflammatory cytokines IFN-γ, IL-6 and TNF-α. Compared with mock transfected L929 (mock-L929) control cells, ICOS-L929 cells promoted significant proliferation of primary cultured TFC, with increased thyroid hormone and Tg production (all P < 0.01). TFC proliferation and production of thyroid hormones and Tg were inhibited significantly in the presence of ICOSL blocking antibody (11 C4) (all P < 0.05). Our observations suggest that ICOS-ICOSL signal plays a direct role in proliferation and differentiation of TFC and may exert important effects in the initiation, maintenance and exaggeration of autoimmune responses in local tissue. [ABSTRACT FROM AUTHOR]

This study investigated the effect of cadmium on the telomerase activity, the expression of TERT, c-myc and p53 and the apoptosis of rat hepatocytes. The rats were administrated 5, 10 and 20 μmol/kg cadmium chloride intraperitoneally and sacrificed 48 h after the initial treatment. The telomerase activity of the rat hepatocytes was measured by the telomeric repeat amplification protocol (TRAP), and apoptosis was detected by flow cytometry. The mRNA expressions of TERT, c-myc and p53 were measured by reverse transcription-polymerase chain reaction (RT-PCR). C-myc and P53 proteins were determined by immunochemistry. The results showed that cadmium chloride increased the hepatocellular telomerase activity in a dose-dependant manner and induced the apoptosis of hepatocytes significantly. The value of relative coefficient between the telomerase activity and the apoptosis rate was 0.9398. RT-PCR revealed that specific bands corresponding to the TERT mRNA, c-myc mRNA, and p53 mRNA were displayed at 185, 342 and 538 bp respectively. Cadmium chloride could substantially increase the mRNA expressions of TERT, c-myc and p53 in rat hepatocytes, as compared with control. Moreover, cadmium chloride at the doses of 5, 10 and 20 μmol/kg could increase the content of P53 protein in rat hepatocytes obviously, but only that at the doses of 10 and 20 μmol/kg substantially promoted the c-myc protein level in rat hepatocytes. Our study herein suggested that cadmium may contribute to the carcinogenesis by activating telomerase, and overexpressing the mRNAs of TERT, c-myc and p53, and causing apoptosis of normal cells. [ABSTRACT FROM AUTHOR]

This paper deals with the robust control problem for a class of uncertain nonlinear networked systems with stochastic communication delays via sliding mode conception (SMC). A sequence of variables obeying Bernoulli distribution are employed to model the randomly occurring communication delays which could be different for different state variables. A discrete switching function that is different from those in the existing literature is first proposed. Then, expressed as the feasibility of a linear matrix inequality (LMI) with an equality constraint, sufficient conditions are derived in order to ensure the globally mean-square asymptotic stability of the system dynamics on the sliding surface. A discretetime SMC controller is then synthesized to guarantee the discrete-time sliding mode reaching condition with the specified sliding surface. Finally, a simulation example is given to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (anti-BPDE) is a metabolite of benzo[a]pyrene (B[a]P) and acts as a potent mutagen in mammalian systems. However, molecular mechanisms related to anti-BPDE-induced carcinogenesis are poorly understood. Here, we investigated the expression of proto-oncogene c- myc in human bronchial epithelial cells (16HBE-T) transformed by exposure to anti-BPDE. The levels of mRNA and protein of c-Myc were examined in the 16HBE-T and vehicletreated control cells (16HBE-N) by using different methods respectively, including reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative real-time PCR (Q-PCR), western blot and immunocytochemical methods. The level of c- myc mRNA appeared to be significantly increased in 16HBE-T, as compared with those of the 16HBE-N. Likewise, the expression of c-Myc protein was significantly enhanced as compared with those of the control cells. Moreover, the localization of c-Myc protein shows mainly nuclear staining in 16HBE-T. In conclusion, the abnormal expression of c-Myc was present in anti-BPDE malignantly transformed 16HBE cells, which may be involved in the carcinogenesis molecular mechanism of anti-BPDE. [ABSTRACT FROM AUTHOR]

In this study, the serum levels, including thyroid hormones free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulating hormone(TSH)among the subjects from the exposed group ( n = 48) and the control group ( n = 45) were detected by immuno radiometric assay (IRMA). The expression levels of TRα1, TRβ1, TSHR mRNA in placentas and umbilical cords were detected by fluorescent quantitative real-time PCR (FQ-PCR). The correlations between the thyroid hormone levels in maternal serum and umbilical serum, and between the expression levels of its receptors mRNA in placentas and umbilical cords were determined. We found that the FT4 levels of both maternal serum and umbilical cord serum in the exposed group were lower than those in the control ( P < 0.05). However, the increased TSH levels in the exposed group had statistically significance compared to those in the control group ( P < 0.05). The TRα1 and TRβ1 mRNA levels both in placentas and umbilical cords in the exposed group were lower than those in the control group ( P < 0.05 and 0.01). However, the TSHR mRNA levels in the exposed group were significantly different compared to those in the control group ( P < 0.01). The serum FT4 and TSH levels of parturient women were positively correlated with those of the newborns in both groups ( P < 0.05 and 0.01). The mRNA levels of TRα1, TRβ1 and TSHR in the placentas were positively correlated with those in umbilical cords in both groups ( P < 0.01). The findings suggest that some environmental pollutants existing in the electronic waste (e-waste) dismantling region may affect the health of local parturient women and newborns, representing changes both in serum levels of thyroid hormones and in mRNA expression of its receptors. [ABSTRACT FROM AUTHOR]

Selenium compounds, as an effective chemopreventive agent, can induce apoptosis in tumor cells. Reactive oxygen species (ROS) are important mediators in apoptosis induced by various stimuli, which include chemopreventive agents. In this study, we investigated the relationship between ROS and the levels of DNA damage induced by selenite in HepG2 cells. After HepG2 cells were treated with selenite, there was a dose-dependent decrease in cell viability. The levels of ROS induced by selenite were measured by 2′, 7′-dichlorofluorescein diacetate (DCFH-DA) fluorescence, which shos a dose-and time-dependent increase in HepG2 cells. The levels of DNA damage in HepG2 increased in all cells treated with an increasing dose of selenite at 0, 2.5, 5, 10, and 20 μmol/L. N-acetylcysteine (NAC), a known antioxidant, increased cell viability and decreased ROS generation. Moreover, NAC effectively blocked DNA damage induced by selenite. These results revealed that ROS might play an important role in selenite-induced DNA damage that can be reduced by NAC treatment. [ABSTRACT FROM AUTHOR]

To study interaction and dose-related effects of mixed cypermethrin and methyl parathion on endocrine and immune functions, 120 Wistar rats were divided randomly into six groups of ten male and ten female rats, respectively, at the age of 2 months. All groups were force-fed every 2 days for 30 days with cypermethrin 0.0, 8.0, 0.0, 8.0, 1.8, 0.4 mg/kg bw and methyl parathion 0.0, 0.0, 0.23, 0.23, 0.0518, 0.0115 mg/kg bw. Controls received vehicle solvent only. Body weight gain and organ weights were measured. Serum or blood were used to test luteinizing hormone, follicle stimulating hormone, estradiol (E2), testosterone, thyroid hormones (T3, T4, TSH), IgG, IgA, rate of neutrophil phagocytosis and of lymphocyte transformation. The effects on relative weights of ovaries and adrenals, IgA and rate of lymphocyte transformation were antagonistic interaction; the effect on estradiol was synergistic in female, whereas addictive in male rats; and the other indices indicated addictive interaction. Organ weights were similar in exposed and control animals except for adrenal (heavier in exposed rats, P<0.01). Serum levels of FSH and estradiol were higher in exposed groups than in controls ( P<0.01). IgG levels were lower in exposed rats than in controls ( P<0.01), and IgA levels were higher in exposed females than in controls ( P<0.01). Lymphocyte transformation rates were lower ( P<0.01) and neutrophil phagocytosis rates were higher ( P<0.01) in exposed rats than in controls. Our results showed that exposure to low-dose mixtures of cypermethrin and methyl parathion may affect hormone levels (especially estradiol) and immune function in rats, and the NOAELs of combined compounds were located at 1/600 LD50. [ABSTRACT FROM AUTHOR]

Primary rat hepatocytes were cultured using differentin vitro models and the enzyme leakage, albumin secretion, and cytochrome P450 1A (CYP 1A) activity were observed. The results showed that the level of LDH was decreased over time in culture. However, on day 5, LDH showed a significant increase in monolayer culture (MC) while after day 8 no LDH was detectable in sandwich culture (SC). The levels of AST and ALT did not change significantly over the investigated time. The CYP 1A activity was gradually decreased in a time-dependent manner in MC and SC. The decline of CYP 1A was faster in MC than in SC. This effect was partially reversed by using cytochrome P450 (CYP450) inducer such as Omeprazol and 3-methylcholanthrene (3-MC) and the CYP 1A induction was always higher in MC than in SC. In bioreactor basic CYP 1A activity was preserved over 2 weeks and the highest albumin production was observed in bioreactor followed by SC and MC. Taken together, it was indicated each investigated model had its advantages and disadvantages. It was also underlined that various in vitro models may address different questions. [ABSTRACT FROM AUTHOR]

Dilution enthalpies, measured using isothermal flow calorimetry, are reported for aqueous solutions of BaCl2 at 300°C and 11.0 MPa, MgCl2, CaCl2, and BaCl2 at 325°C and 14.8 MPa, and at 350°C and 17.6 MPa. Previously collected dilution enthalpies for aqueous solutions of MgCl2 and CaCl2 at 300°C and 10.3 MPa and for aqueous solutions of HCl at 250, 275, and 300°C at 10.3 MPa and 320°C at 12.8 MPa were included with the new data at 300°C and 11.0 MPa and at 350°C and 17.6 MPa when fitting the Pitzer parameters. The concentration range of the chloride solutions was 0.5 to 0.02 molal. Parameters for the Pitzer excess Gibbs ion–interaction equation were determined from the fits of the experimental heat data. Equilibrium constants, enthalpy changes, entropy changes, and heat-capacity changes for the association of alkaline earth metal ions and H+ with chloride ion were estimated from the heat data. For all systems, the enthalpy and entropy changes are positive and show accelerating increases with temperature. The resulting equilibrium constants show significant, but smaller, increases with temperature. [ABSTRACT FROM AUTHOR]

Dilution enthalpies, measured using isothermal flow calorimetry, are reported for aqueous solutions of KOH and CsOH at 300°C and 11.0 MPa, 325°C and 14.8 MPa, and for aqueous solutions of NaOH, KOH, and CsOH at 350°C and 17.6 MPa. Previously collected dilution enthalpies for aqueous solutions of NaOH at 300°C and 9.3 MPa and at 325°C and 12.4 MPa were included when fitting the Pitzer parameters. The concentration range of the hydroxide solutions was 0.5–0.02 molal. Parameters for the Pitzer excess Gibbs ion-interaction equation were determined from the fits of the experimental heat data. Equilibrium constants, enthalpy changes, entropy changes, and heat capacity changes for alkali metal ion association with hydroxide ion were estimated from the heat data. For all systems, the enthalpy changes and entropy changes were positive and had accelerating increases with temperature. The resulting equilibrium constants show significant, but smaller, increases with temperature. [ABSTRACT FROM AUTHOR]

Dilution enthalpies, measured using isothermal flow calorimetry, are reported for aqueous solutions of LiCl, KCl, and CsCl at 300°C and 11.0 MPa, 325°C and 14.8 MPa, and 350°C and 17.6 MPa. The concentration range of the chloride solutions was 0.5 to 0.02 m. Parameters for the Pitzer excess Gibbs ion-interaction equation were determined from the fits of the experimental heat data. Equilibrium constants, enthalpy changes, entropy changes, and heat capacity changes for ion association of the chloride salts were estimated from the heat data. For all systems, the enthalpy and entropy changes were positive and had accelerating increases with temperature. The resulting equilibrium constants show significant, but smaller, increases with temperature. [ABSTRACT FROM AUTHOR]