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The use of silver nanoparticles in medical and consumer products such as wound dressings, clothing and cosmetic has increased significantly in recent years. Still, the influence of these particles on our health and especially on our brain, has not been examined adequately up to now. We studied the influence of AgEO- (Ethylene Oxide) and AgCitrate-Nanoparticles (NPs) on the protective barriers of the brain, namely the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (blood-CSF) barrier in vitro. The NPs toxicity was evaluated by examining changes in membrane integrity, cell morphology, barrier properties, oxidative stress and inflammatory reactions. AgNPs decreased cell viability, disturbed barrier integrity and tight junctions and triggered oxidative stress and DNA strand breaks. However, all mentioned effects were, at least partly, suppressed by a Citrate-coating and were most pronounced in the cells of the BBB as compared to the epithelial cells representing the blood-CSF barrier. AgEO- but not AgCitrate-NPs also triggered an inflammatory reaction in porcine brain capillary endothelial cells (PBCEC), which represent the BBB.
Our data indicate that AgNPs may cause adverse effects within the barriers of the brain, but their toxicity can be reduced by choosing an appropriate coating material.
Green algae are of great economic importance. Seaweed is consumed fresh or as seasoning in Japan. The commercial value is determined by quality, color, and flavor and is also strongly influenced by the production area. Our research, based on solid phase microextraction gas chromatography mass spectrometry (SPME-GC-MS), has revealed that volatile compounds differ intensely in the four varieties of commercial green algae. Accordingly, 41 major volatile compounds were identified. Heptadecene was the most abundant compound from Okayama (Ulva prolifera), Tokushima (Ulva prolifera), and Ehime prefecture (Ulva linza). Apocarotenoids, such as ionones, and their derivatives were prominent volatiles in algae from Okayama (Ulva prolifera) and Tokushima prefecture (Ulva prolifera). Volatile, short chained apocarotenoids are among the most potent flavor components and contribute to the flavor of fresh, processed algae, and algae-based products. Benzaldehyde was predominant in seaweed from Shizuoka prefecture (Monostroma nitidum). Multivariant statistical analysis (PCA) enabled simple discrimination of the samples based on their volatile profiles. This work shows the potential of SPME-GC-MS coupled with multivariant analysis to discriminate between samples of different geographical and botanical origins and form the basis for development of authentication methods of green algae products, including seasonings.
Arsenic-containing hydrocarbons are one group of fat-soluble organic arsenic compounds (arsenolipids) found in marine fish and other seafood. A risk assessment of arsenolipids is urgently needed, but has not been possible because of the total lack of toxicological data. In this study the cellular toxicity of three arsenic-containing hydrocarbons was investigated in cultured human bladder (UROtsa) and liver (HepG2) cells. Cytotoxicity of the arsenic-containing hydrocarbons was comparable to that of arsenite, which was applied as the toxic reference arsenical. A large cellular accumulation of arsenic, as measured by ICP-MS/MS, was observed after incubation of both cell lines with the arsenolipids. Moreover, the toxic mode of action shown by the three arsenic-containing hydrocarbons seemed to differ from that observed for arsenite. Evidence suggests that the high cytotoxic potential of the lipophilic arsenicals results from a decrease in the cellular energy level. This first in vitro based risk assessment cannot exclude a risk to human health related to the presence of arsenolipids in seafood, and indicates the urgent need for further toxicity studies in experimental animals to fully assess this possible risk.
Background: DNA-methylation is a common epigenetic tool which plays a crucial role in gene regulation and is essential for cell differentiation and embryonic development. The placenta is an important organ where gene activity can be regulated by epigenetic DNA modifications, including DNA methylation. This is of interest as, the placenta is the interface between the fetus and its environment, the mother. Exposure to environmental toxins and nutrition during pregnancy may alter DNA methylation of the placenta and subsequently placental function and as a result the phenotype of the offspring. The aim of this study was to develop a reliable method to quantify DNA methylation in large clinical studies. This will be a tool to analyze the degree of DNA methylation in the human placenta in relationship to clinical readouts. Methods: Liquid chromatography-electrospray ionization/multi-stage mass spectrometry (LC-ESI/MS/MS) technique was used for the quantification of the 5dmC/dG ratio in placentas from 248 healthy pregnancies. We were able to demonstrate that this method is a reliable and stable way to determine global placental DNA methylation in large clinical trials. Results/Conclusion: The degree of placental DNA methylation seen in our pilot study varies substantially from 2% to 5%. The clinical implications of this variation need to be demonstrated in adequately powered large studies.
Background: Cardiovascular diseases are the leading cause of death in developed countries. The underlying mechanism is often atherosclerotic remodeling of blood vessels in organs such as heart, kidney, brain, and large arteries in case of peripheral arterial disease. Beside environmental and behavioral factors such as smoking or lack of physical activity, genetic variants in genes involved in lipid metabolism, blood pressure regulation, oxidative stress, and coagulation play a prominent role in the pathogenesis of atherosclerosis.
Methods: Thus, we developed and validated for clinical use and research a macroarray system for the simultaneous detection of key genetic variants in genes involved in lipid metabolism, blood pressure regulation, oxidative stress, and coagulation.
Results: When compared with standard PCR technologies to determine all these genetic variants in parallel, the macroarray system (MutaCHIP (R) ARTERO) was as accurate but faster, cheaper, and easier to handle compared to classical real time PCR based technologies.
Conclusions: MutaCHIP (R) ARTERO is a gene chip for diagnostics of a complex genetic panel involved in the pathogenesis of atherosclerosis. This method is as sensitive and precise as real time PCR and is able to replicate real time PCR data previously validated in evaluation studies.
Beckground: Evaluate the efficacy and safety of telbivudine during the 2nd and 3rd trimester of pregnancy in intrauterine transmission of hepatitis B virus (HBV). Based on the principle of Cochrane systematic reviews, a database was constructed from Medline, EMBASE, Cochrane Library, the US National Science Digital Library (NSDL), the China Biological Medicine Database (CBM-disc), and contact with Chinese experts in the field from November 2006 to February 2013.
Results: Either the Mantel-Haenszel or Inverse Variance fixed-effects model or Mantel-Haenszel or Inverse Variance random-effects model was applied for all analyses indicated by odds ratio (OR) and 95% confidence interval (CI). The meta-analysis based on new onset of HBsAg seropositivity of infants at 6 - 12 months postpartum revealed that the control group had an intrauterine transmission rate of 8.25 - 42.31%. This rate was reduced to 0 - 14.29% in the telbivudine treatment group (OR 0.09, 95% CI 0.04 - 0.22, including seven trials, p < 0.001). The rates of intrauterine transmission based on new onset of HBV DNA seropositivity of infants at 6 - 12 months postpartum were 8.25 - 19.23% in the control group and 0 - 3.57% in the treatment group (OR 0.07, 95% CI 0.02 - 0.22, p < 0.001, including only five trials, since two trials had no data on HBV DNA in infants). With the exception of CK elevations, adverse effect frequencies were similar in both groups.
Conclusions: Telbivudine is an effective and safe drug for preventing intrauterine transmission of HBV.
Background: Scrub typhus is a potentially fatal infectious disease caused by Orientia tsutsugamushi. There is little attention given to hepatic impairment in the adults with scrub typhus. This study investigated the incidence and the prognostic implications of hepatic impairment in patients with scrub typhus.
Methods: We retrospectively reviewed a total of 143 adult patients with scrub typhus who were admitted between January 1999 and December 2010 in Guangdong province, China. The patients were divided into three groups, e.g., normal, mild, and moderate to severe groups based on the elevated serum ALT and/or total bilirubin levels. Furthermore, clinical characteristics and prognosis of the patient groups were compared.
Results: 109 patients (76.2%) had abnormal liver function. Among the patients with hepatic impairment 45 cases (31.4%), 54 cases (37.8%), and 10 cases (7.0%) had mild, moderate, and severe hepatic damage, respectively. The moderate to severe hepatic impairment group had higher levels of serum creatinine compared with that of normal hepatic function. The incidence of new onset of renal dysfunction - defined as peak serum creatinine >= 176 mu mol/L during hospital stay with no evidence of renal disease prior hospitalization - was 0% in the mild hepatic impairment group, 8.9% in the moderate hepatic impairment group, and 21.9% in the severe hepatic impairment group, (p = 0.005 for trend). Additionally, the patients with hepatic impairment (n = 109) had higher incidences of episodes of thrombocytopenia (45.9% vs. 8.82%, p < 0.001), hypoalbuminemia (50.5% vs. 11.8%, p < 0.001), new onset of renal dysfunction (16.5% vs. 0.0%, p = 0.011), and electrocardiogram abnormality (28.4% vs. 8.82%, p = 0.019) than the patients without hepatic impairment.
Conclusions: The degree of hepatic impairment induced by scrub typhus is associated with new onset of renal dysfunction.
Insulin resistance is a complex metabolic disorder in which insulin-sensitive tissues fail to respond to the physiological action of insulin. There is a strong correlation of insulin resistance and the development of type 2 diabetes both reaching epidemic proportions. Dysfunctional lipid metabolism is a hallmark of insulin resistance and a risk factor for several cardiovascular and metabolic disorders. Numerous studies in humans and rodents have shown that insulin resistance is associated with elevations of non-esterified fatty acids (NEFA) in the plasma. Moreover, bioactive lipid intermediates such as diacylglycerol (DAG) and ceramides appear to accumulate in response to NEFA, which may interact with insulin signaling. However, recent work has also indicated that sphingosine 1-phosphate (S1P), a breakdown product of ceramide, modulate insulin signaling in different cell types. In this review, we summarize the current state of knowledge about S1P and insulin signaling in insulin sensitive cells. A specific focus is put on the action of S1P on hepatocytes, pancreatic beta-cells and skeletal muscle cells. In particular, modulation of S1P-signaling can be considered as a potential therapeutic target for the treatment of insulin resistance and type 2 diabetes.
Dealing with large sample sizes: comparison of a new one spot dot blot method to western blot
(2014)
Background: Western blot is the gold standard method to determine individual protein expression levels. However, western blot is technically difficult to perform in large sample sizes because it is a time consuming and labor intensive process. Dot blot is often used instead when dealing with large sample sizes, but the main disadvantage of the existing dot blot techniques, is the absence of signal normalization to a housekeeping protein.
Methods: In this study we established a one dot two development signals (ODTDS) dot blot method employing two different signal development systems. The first signal from the protein of interest was detected by horseradish peroxidase (HRP). The second signal, detecting the housekeeping protein, was obtained by using alkaline phosphatase (AP).
Results: Inter-assay results variations within ODTDS dot blot and western blot and intra-assay variations between both methods were low (1.04 - 5.71%) as assessed by coefficient of variation.
Conclusions: ODTDS dot blot technique can be used instead of western blot when dealing with large sample sizes without a reduction in results accuracy.
Background/Aims: Diabetes is well-known to influence endothelial function. Endothelial function and blood flow regulation might be different in diabetic and non-diabetic pregnancy. However, the impact of umbilical blood flow regulation in gestational diabetes on fetal development is unknown so far. Methods: In a prospective birth cohort study, we analyzed the association of the umbilical artery Doppler indices (pulsatility index, resistance index and systolic/diastolic ratio) and fetal size measures (biparietal diameter, head circumference, abdominal circumference, femur length and birth weight) in 519 non-gestational diabetes mellitus pregnancies (controls) and 226 gestational diabetes mellitus pregnancies in middle (day 160.32 +/- 16.29 of gestation) and late (day 268.12 +/- 13.04 of gestation) pregnancy. Results: Multiple regression analysis considering confounding factors (gestational day of ultrasound examination, offspring sex, maternal body mess index before pregnancy, maternal age at delivery, maternal body weight at delivery and maternal hypertension) showed that umbilical artery Doppler indices (pulsatility index, resistance index and systolic/diastolic ratio) were associated with fetal head circumference and femur length in middle gestational diabetes mellitus pregnancy but not in non-gestational diabetes mellitus pregnancy. Head circumference, biparietal diameter, abdominal circumference and femur length in mid gestation were smaller in fetus of gestational diabetes mellitus pregnancy versus non-gestational diabetes mellitus pregnancy. In contrast to non-gestational diabetes mellitus pregnancy in late gestation, umbilical artery Doppler indices in gestational diabetes mellitus pregnancy were not associated with ultrasound measures of fetal growth. Birth weight was slightly increased in gestational diabetes mellitus pregnancy as compared to non-gestational diabetes mellitus pregnancy. Conclusions: The impact of umbilical blood flow on fetal growth is time dependent in human gestational diabetes mellitus and non-gestational diabetes mellitus pregnancy. In gestational diabetes mellitus pregnancy umbilical blood flow is critical for organ development in much earlier stages of pregnancy as compared to non-gestational diabetes mellitus pregnancy. The physiological and molecular pathways why there is a catch up growth in later times of gestational diabetes mellitus pregnancy resulting in larger gestational diabetes mellitus babies at birth needs to be addressed in further studies.