Effect of far-infrared radiation therapy on von Willebrand factor in patients with chronic kidney disease.

Background: Hemostatic abnormality has contributed to vascular access thrombosis in patients with chronic kidney disease (CKD). Previous studies have demonstrated that far-infrared radiation (FIR) therapy can maintain the patency and maturity of arteriovenous fistulas of patients undergoing hemodialysis (HD). However, prolonged access bleeding is observed once FIR is conducted at the end of dialysis. FIR can block the binding of platelet and von Willebrand factor (vWF), a predictor of hemostatic abnormality and vascular access thrombosis. However, clinical studies exploring FIR and vWF are sparse. Methods: We recruited 20 HD patients, 21 CKD patients, and 20 controls to examine the alteration of vWF and a disintegrin and metalloproteinase with thrombospondin type 1 repeats 13 (ADAMTS13) following a single 40-min session of FIR therapy. In addition, the alteration of these factors in the HD group was examined following a 40-min FIR session thrice a week for 3 months. Results: A decreasing trend in the vWF activity-antigen ratio of participants in all groups following a single FIR session was observed. In addition, the ratio in the HD group was significantly lower following 3 months of FIR therapy. The subgroup analysis revealed a consistent trend and multiple regression analysis showed that participants not taking hydroxymethylglutaryl-coenzyme A reductase inhibitor, diabetes mellitus, and higher hemoglobin levels were the significant factors. The alteration of the vWF activity-antigen ratio correlated moderately to that of ADAMTS13 antigen and activity. Conclusion: FIR may alter the ratio of ultra-large vWF multimers through ADAMTS13, contributing to inhibiting platelet-endothelium interactions of CKD patients.

Protective effect of microorganism biotransformation-produced resveratrol on the high fat diet-induced hyperlipidemia, hepatic steatosis and synaptic impairment in hamsters.

Background: Resveratrol, a natural antioxidant polyphenol, has the functions of anti-inflammation, anti-cancer, liver protection and cardioprotection. Microorganism biotransformation-produced resveratrol (MBR) product shows higher purity than the natural source of resveratrol and costs less than the chemically synthesized resveratrol. The aim of the present study was to investigate the protective effects of MBR in hamsters treated with a high-fat diet (HFD). Methods: MBR was obtained by the fermentative process of piceid. Hamsters were randomly divided into four groups: HFD plus oral administration of MBR 0 (C), 5 (L), 20 (M) or 50 mg/kg (H), respectively. After six-week of treatment, hamsters were sacrificed, and tissues were collected for further analysis. Results: MBR at these three dosages did not influence the appetite or growth of the hamsters. Liver enzymes, blood glucose, total cholesterol, triglyceride, and liver weight were significantly reduced in the MBR groups than in the control group. Additionally, high-density lipoprotein-cholesterol (HDL-C) was also elevated in all MBR groups. On the other hand, serum low-density lipoprotein-cholesterol (LDL-C) was decreased in the MBR groups. Triglyceride (TG) in liver tissue and fatty liver level were lower in group H. Memory-associated proteins, phosphorylation of calmodulin-dependent protein kinase II (p-CaMK II) and synaptophysin (SYP), were increased in the brains of MBR groups. Conclusion: The high yield- and short procedure-produced MBR has the potential to protect animals fed with HFD from hyperlipidemia, hepatic steatosis, hyperglycemia, and synaptic impairment, which might be beneficial for patients with these types of diseases.

Elevated Nitrite/Nitrate Ratio as a Potential Biomarker for the Differential Diagnosis of Pleural Effusions.

Pleural effusions (PEs) are common in clinical practice and can be due to many different underlying diseases such as cancer, congestive heart failure, or pneumonia. An accurate differential diagnostic categorization is essential, as the treatment and prognosis of PEs largely depend on its cause. In this study, we tested the hypothesis that nitrite and nitrate concentrations in PEs are associated with the inflammation and infection conditions. We therefore measured the nitrite and nitrate levels in 143 PE samples using a sensitive liquid chromatography-tandem mass spectrometry method and investigated their diagnostic potential in differentiating PEs. The results showed that nitrite concentrations and nitrite/nitrate ratios were higher in exudates than in transudates (NO2-: 2.12 vs. 1.49 µM; NO2-/NO3-: 23.3 vs. 14.0). Both the nitrite concentrations and the nitrite/nitrate ratios were positively correlated with the three Light's criteria. Moreover, the receiver operating characteristic curve analysis revealed that the nitrite/nitrate ratio with an area under the curve of 0.71 could be a potential diagnostic biomarker in separating infectious PEs (IPEs) from other types of PEs. Taken together, the nitrite/nitrate ratio not only reflected the statuses of inflammation, but also the nitrate reduction by pathogenic bacteria infection in the pleural cavity. The nitrite/nitrate ratio could be a better biomarker in the differential diagnosis of PEs than the nitrite concentration alone.

COVID-19 Vaccines in Patients with Maintenance Hemodialysis.

The COVID-19 pandemic has infected more than 180 million people and caused more than 3.95 million deaths worldwide. In addition to personal hygiene, augmented cleaning, social distancing, and isolation, vaccine development and immunization are essential for this highly contagious disease. Patients with maintenance hemodialysis (MHD) have a greater risk of COVID-19 infection owing to their comorbidities, defective immunity, and repeated crowded in-center dialysis settings. However, many patients hesitate to get vaccinated because of their misunderstandings. The Efficacy of COVID-19 vaccination has been intensively discussed in the general population, whereas the data concerning the effectiveness of vaccination in MHD patients are relatively scanty. Nevertheless, those limited publications can provide some valuable information. Overall, lower and more delayed antibody responses following COVID-19 vaccination were observed in patients with MHD than in healthy controls in the settings of different populations, vaccines and dosage, definitions of the immune response, and antibody detection timepoints. Younger age, previous COVID-19 infection, and higher serum albumin level were positively associated with antibody formation, whereas older age and receiving immunosuppressive therapy were unfavorable factors. However, it remains uncertain between the elicited antibodies following vaccination and the genuine protection against COVID-19 infection. Patients with MHD should make their COVID-19 vaccination a priority in addition to other protective measures. More studies focusing on different vaccines, non-humoral immune responses, and risk-benefit analyses are warranted.

4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene, a Major Active Metabolite of Bisphenol A, Triggers Pancreatic ß-Cell Death via a JNK/AMPKα Activation-Regulated Endoplasmic Reticulum Stress-Mediated Apoptotic Pathway.

4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP), a major active metabolite of bisphenol A (BPA), is generated in the mammalian liver. Some studies have suggested that MBP exerts greater toxicity than BPA. However, the mechanism underlying MBP-induced pancreatic ß-cell cytotoxicity remains largely unclear. This study demonstrated the cytotoxicity of MBP in pancreatic ß-cells and elucidated the cellular mechanism involved in MBP-induced ß-cell death. Our results showed that MBP exposure significantly reduced cell viability, caused insulin secretion dysfunction, and induced apoptotic events including increased caspase-3 activity and the expression of active forms of caspase-3/-7/-9 and PARP protein. In addition, MBP triggered endoplasmic reticulum (ER) stress, as indicated by the upregulation of GRP 78, CHOP, and cleaved caspase-12 proteins. Pretreatment with 4-phenylbutyric acid (4-PBA; a pharmacological inhibitor of ER stress) markedly reversed MBP-induced ER stress and apoptosis-related signals. Furthermore, exposure to MBP significantly induced the protein phosphorylation of JNK and AMP-activated protein kinase (AMPK)α. Pretreatment of ß-cells with pharmacological inhibitors for JNK (SP600125) and AMPK (compound C), respectively, effectively abrogated the MBP-induced apoptosis-related signals. Both JNK and AMPK inhibitors also suppressed the MBP-induced activation of JNK and AMPKα and of each other. In conclusion, these findings suggest that MBP exposure exerts cytotoxicity on ß-cells via the interdependent activation of JNK and AMPKα, which regulates the downstream apoptotic signaling pathway.

Roles of ERK/Akt signals in mitochondria-dependent and endoplasmic reticulum stress-triggered neuronal cell apoptosis induced by 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene, a major active metabolite of bisphenol A.

Bisphenol A (BPA) is recognized as a harmful pollutant in the worldwide. Growing studies have reported that BPA can cause adverse effects and diseases in human, and link to a potential risk factor for development of neurodegenerative diseases (NDs). 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP), which generated in the mammalian liver after BPA exposure, is a major active metabolite of BPA. MBP has been suggested to exert greater toxicity than BPA. However, the molecular mechanism of MBP on the neuronal cytotoxicity remains unclear. In this study, MBP exposure significantly reduced Neuro-2a cell viability and induced apoptotic events that MBP (5-15 µM) exhibited greater neuronal cytotoxicity than BPA (50-100 µM). The mitochondria-dependent apoptotic signals including the decrease in mitochondrial membrane potential (MMP) and the increase in cytosolic apoptosis-induced factor (AIF), cytochrome c release, and Bax protein expression were involved in MBP (10 µM)-induced Neuro-2a cell death. Exposure of Neuro-2a cells to MBP (10 µM) also triggered endoplasmic reticulum (ER) stress through the induction of several key molecules including glucose-regulated protein (GRP)78, C/EBP homologous protein (CHOP), X-box binding protein (XBP)-1, protein kinase R-like ER kinase (PERK), eukaryotic initiation factor 2α (eIF2α), inositol-requiring enzyme(IRE)-1, activation transcription factor(AFT)4 and ATF6, and caspase-12. Pretreatment with 4-PBA (an ER stress inhibitor) and specific siRNAs for GRP78, CHOP, and XBP-1 significantly suppressed the expression of these ER stress-related proteins and the activation of caspase-12/-3/-7 in MBP-exposed Neuro-2a cells. Furthermore, MBP (10 µM) exposure dramatically increased the activation of extracellular regulated protein (ERK)1/2 and decreased Akt phosphorylation. Pretreatment with PD98059 (an ERK1/2 inhibitor) and transfection with the overexpression of activation of Akt1 (myr-Akt1) effectively suppressed MBP-induced apoptotic and ER stress-related signals. Collectively, these results demonstrate that MBP exposure exerts neuronal cytotoxicity via the interplay of ERK activation and Akt inactivation-regulated mitochondria-dependent and ER stress-triggered apoptotic pathway, which ultimately leads to neuronal cell death.

15N-labelled nitrite/nitrate tracer analysis by LC-MS/MS: Urinary and fecal excretion of nitrite/nitrate following oral administration to mice.

Determination of the modulation of nitrite and nitrate levels in biological samples usually poses a major challenge, owing to their high background concentrations. To effectively investigate the variation of nitrite/nitrate in vivo, in this study, we developed a15N-labelled nitrite/nitrate tracer analysis using LC-MS/MS following the derivatization with 2,3-diaminonaphthalene. This method allows for the determination of 15N-labelled nitrite/nitrate as 15N-2,3-naphthotriazole (15N-NAT) that can efficiently differentiate newly introduced nitrite/nitrate from the background nitrite/nitrate in biological matrices. We also investigated the contribution of background 14N-NAT isotopomers to 15N-NAT, which has long been overlooked in the literature. Our results indicated that the contribution of background 14N-NAT isotopomers to 15N-NAT is significant. Such contribution is constant (~2.2% under positive ion mode and 1.1% under negative ion mode), and does not depend upon the concentration of 14N-NAT or the sample matrix measured. An equation has been therefore developed, for the first time, to correct the contribution of background 14N-NAT isotopomers to 15N-NAT. With the proposed 15N-labelled nitrite/nitrate tracer analysis, the amount and percentage distribution of 15NO2- and 15NO3-, both in urine and feces, after oral administration of 15N-labelled nitrite/nitrate are clearly demonstrated. The excretions of 15NO2- and 15NO3- were significantly increased with the increasing dose implying that the dietary nitrite/nitrate intake is an important source in urine/feces. The present method allows for the simple, reliable and accurate quantification of 15NO2- and 15NO3-, and it should also be useful to trace the biotransformation of nitrite and nitrate in vivo.

Methylmercury exposure induces ROS/Akt inactivation-triggered endoplasmic reticulum stress-regulated neuronal cell apoptosis.

Epidemiological studies have positively linked mercury exposure and neurodegenerative diseases (ND). Methylmercury (MeHg), an organic form of mercury, is a ubiquitous and potent environmental neurotoxicant that easily crosses the blood-brain barrier and causes irreversible injury to the central nervous system (CNS). However, the molecular mechanisms underlying MeHg-induced neurotoxicity remain unclear. Here, the present study found that Neuro-2a cells underwent apoptosis in response to MeHg (1-5 µM), which was accompanied by increased phosphatidylserine (PS) exposure on the outer cellular membrane leaflets, caspase-3 activity, and the activation of caspase cascades and poly (ADP-ribose) polymerase (PARP). Exposure of Neuro-2a cells to MeHg also triggered endoplasmic reticulum (ER) stress, which was identified via several key molecules (including: glucose-regulated protein (GRP)78, GRP94, C/EBP homologous protein (CHOP) X-box binding protein(XBP)-1, protein kinase R-like ER kinase (PERK), eukaryotic initiation factor 2α (eIF2α), inositol-requiring enzyme(IRE)-1, activation transcription factor(AFT)4, and ATF6. Transfection with GRP78-, GRP94-, CHOP-, and XBP-1-specific small interfering (si)RNA significantly suppressed the expression of these proteins, and attenuated cytotoxicity and caspase-12, -7, and -3 activation in MeHg-exposed cells. Furthermore, MeHg dramatically decreased Akt phosphorylation, and the overexpression of activation of Akt1 (myr-Akt1) could significantly prevent MeHg-induced Akt inactivation, as well as apoptotic and ER stress-related signals. Pretreatment with the antioxidant N-acetylcysteine (NAC) effectively prevented MeHg-induced neuronal cell reactive oxygen species (ROS) generation, apoptotic and ER stress-related signals, and Akt inactivation. Collectively, these results indicate that MeHg exerts its cytotoxicity in neurons by inducing ROS-mediated Akt inactivation up-regulated ER stress, which induces apoptosis and ultimately leads to cell death.

Prehemodialysis arteriovenous access creation is associated with better cardiovascular outcomes in patients receiving hemodialysis: a population-based cohort study.

BACKGROUND: Cardiovascular (CV) disease contributes to nearly half of the mortalities in patients with end-stage renal disease. Patients who received prehemodialysis arteriovenous access (pre-HD AVA) creation had divergent CV outcomes. METHODS: We conducted a population-based cohort study by recruiting incident patients receiving HD from 2001 to 2012 from the Taiwan National Health Insurance Research Database. Patients' characteristics, comorbidities, and medicines were analyzed. The primary outcome of interest was major adverse cardiovascular events (MACEs), defined as hospitalization due to acute myocardial infarction, stroke, or congestive heart failure (CHF) occurring within the first year of HD. Secondary outcomes included MACE-related mortality and all-cause mortality in the same follow-up period. RESULTS: The patients in the pre-HD AVA group were younger, had a lower burden of underlying diseases, were more likely to use erythropoiesis-stimulating agents but less likely to use renin-angiotensin-aldosterone system blockers. The patients with pre-HD AVA creation had a marginally lower rate of MACEs but a significant 35% lower rate of CHF hospitalization than those without creation (adjusted hazard ratio (HR) 0.65, 95% confidence interval (CI) [0.48-0.88]). In addition, the pre-HD AVA group exhibited an insignificantly lower rate of MACE-related mortality but a significantly 52% lower rate of all-cause mortality than the non-pre-HD AVA group (adjusted HR 0.48, 95% CI [0.39-0.59]). Sensitivity analyses obtained consistent results. CONCLUSIONS: Pre-HD AVA creation is associated with a lower rate of CHF hospitalization and overall death in the first year of dialysis.

The Protective Role of GMI, an Immunomodulatory Protein From Ganoderma microsporum, on 5-Fluorouracil-Induced Oral and Intestinal Mucositis.

5-Fluorouracil (5-FU) is used in the treatment of head and neck cancer patients. However, adverse effects experienced such as mucositis and poor appetite may lead to interruption in chemotherapy. The aim of this study is to evaluate the efficacy of GMI, one fungal immunomodulatory protein found in Ganoderma microsporum, for mucositis induced by 5-FU in a mouse model. Mice were administered 5-FU intraperitoneally for 4 days per cycle for a total of 2 chemotherapy cycles. In addition, mice were pretreated with GMI or phosphate-buffered saline 3 days before 5-FU intraperitoneal injection and daily until day 14. On histological analysis, GMI prevented 5-FU-induced damage to the intestinal mucosa and tongue epithelium. We also demonstrated that GMI enhanced the cytotoxicity of 5-FU in 2 oral cancer cell lines, while GMI could not promote this effect in an oral normal cell. In conclusion, GMI alleviates 5-FU-induced damage and decelerates cell death in normal alimentary tract tissue.

Factors affecting fistula failure in patients on chronic hemodialysis: a population-based case-control study.

BACKGROUND: With advancement of hemodialysis (HD) technique, late fistula failure (LFF) remains a problem significantly affecting life quality of patients. We attempt to identify factors affecting LFF in patients on chronic HD in Taiwan from the National Health Insurance Research Database. METHODS: This case-control study enrolled patients over 18 years old and who received regular HD for more than 3 months. LFF was defined as the first fistula failure episode beyond 3 months of chronic HD. We analyzed characteristics, comorbidities and medicine and investigated the association factors of LFF by logistic regression model. A trend test was conducted for risk in different provider levels. Sensitivity tests were conducted to test consistency. RESULTS: Of 1558 patients recruited, 772 (49.6%) were identified as LFF cases and 786 were identified as controls. The data showed that patients with diabetes mellitus (DM) had 42% increased rate of LFF. Patients receiving more than 10 HD sessions per month had a 90% increased rate of LFF; patients receiving chronic HD in private clinics had a 49% reduction rate of LFF. There were no significant differences in age, dialysis frequency, and comorbidities among different provider levels. There was a significant trend of risk reduction of the event from medical centers, regional hospitals, district hospitals, to private clinics. The sensitivity tests revealed similar results. CONCLUSIONS: The factors associated with LFF include DM and receiving more HD sessions; on the contrary, receiving HD in private clinics is associated with less risk of LFF.

Physicochemistry and cardiovascular toxicity of metal fume PM2.5: a study of human coronary artery endothelial cells and welding workers.

Occupational exposure to welding fumes causes a higher incidence of cardiovascular disease; however, the association remains unclear. To clarify the possible association, exposure assessment of metal fumes with an aerodynamic diameter of <2.5 µm (PM2.5) in welding and office areas was characterized in a shipyard in Taiwan. Cardiovascular toxicity caused by PM2.5 was determined in workers (in both the welding and office areas). Significant amounts of bimodal metal fume particles with count median diameters (CMDs) of 14.1~15.1 and 126.3~135.8 nm were produced in the shipyard. Metal fume PM2.5 resulted in decreased cell viability and increased levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), interleukin (IL)-6, and nitric oxide (NO) in human coronary artery epithelial cells (HCAECs). We recruited 118 welding workers and 45 office workers for a personal PM2.5 exposure assessment and determination of urinary levels of 8-OHdG, 8-iso-prostaglandin F2α (8-iso-PGF2α), and various metals. We observed that a 10-µg/m(3) increase in the mean PM2.5 concentration was associated with a 2.15% increase in 8-OHdG and an 8.43% increase in 8-iso-PGF2α in welding workers. Both 8-OHdG and 8-iso-PGF2α were associated with Fe and Zn in the urine. In conclusion, metal fume PM2.5 could increase the risk of cardiovascular toxicity after inhalation.

Molybdenum induces pancreatic ß-cell dysfunction and apoptosis via interdependent of JNK and AMPK activation-regulated mitochondria-dependent and ER stress-triggered pathways.

Molybdenum (Mo), a well-known toxic environmental and industrial pollutant, causes adverse health effects and diseases in humans and has received attention as a potential risk factor for DM. However, the roles of Mo in the mechanisms of the toxicological effects in pancreatic ß-cells are mostly unclear. In this study, the results revealed dysfunction of insulin secretion and apoptosis in the pancreatic ß-cell-derived RIN-m5F cells and the isolated mouse islets in response to Mo. These effects were accompanied by a mitochondria-dependent apoptotic signals including a decreased in the MMP, an increase in cytochrome c release, and the activation of caspase cascades and PARP. In addition, ER stress was triggered as indicated by several key molecules of the UPR. Furthermore, exposure to Mo induced the activation of ERK1/2, JNK, AMPKα, and GSK3-α/ß. Pretreatment with specific pharmacological inhibitors (in RIN-m5F cells and isolated mouse islets) of JNK (SP600125) and AMPK (Compound C) or transfection with si-RNAs (in RIN-m5F cells) specific to JNK and AMPKα effectively prevented the Mo-induced apoptosis and related signals, but inhibitors of ERK1/2 and GSK3-α/ß (PD98059 and LiCl, respectively) did not reverse the Mo-induced effects. Additionally, both the inhibitors and specific si-RNAs could suppress the Mo-induced phosphorylation of JNK and AMPKα each other. Taken together, these results suggest that Mo exerts its cytotoxicity on pancreatic ß-cells by inducing dysfunction and apoptosis via interdependent JNK and AMPK activation downstream-regulated mitochondrial-dependent and ER stress-triggered apoptosis pathways.

Environmentally relevant concentration of arsenic trioxide and humic acid promoted tumor progression of human cervical cancer cells: In vivo and in vitro studies.

In a previous study, treatment at higher concentrations of arsenic trioxide or co-exposure to arsenic trioxide and humic acid was found to be inhibited cell growth of cervical cancer cells (SiHa cells) by reactive oxygen species generation. However, treatment at lower concentrations slightly increased cell viability. Here, we investigate the enhancement of progression effects of environmentally relevant concentration of humic acid and arsenic trioxide in SiHa cell lines in vitro and in vivo by measuring cell proliferation, migration, invasion, and the carcinogenesis-related protein (MMP-2, MMP-9, and VEGF-A) expressions. SiHa cells treated with low concentrations of humic acid and arsenic trioxide alone or in co-exposure significantly increased reactive oxygen species, glutathione levels, cell proliferation, scratch wound-healing activities, migration abilities, and MMP-2 expression as compared to the untreated control. In vivo the tumor volume of either single drug (humic acid or arsenic trioxide) or combined drug-treated group was significantly larger than that of the control for an additional 45 days after tumor cell injection on the back of NOD/SCID mice. Levels of MMP-2, MMP-9, and VEGF-A, also significantly increased compared to the control. Histopathologic effects of all tumor cells appeared round in cell shape with high mitosis, focal hyperkeratosis and epidermal hyperplasia in the skin, and some tumor growth in the muscle were observed. Our results may indicate that exposure to low concentrations of arsenic trioxide and humic acid is associated with the progression of cervical cancer. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1121-1132, 2016.

Cantharidin Induces Apoptosis Through the Calcium/PKC-Regulated Endoplasmic Reticulum Stress Pathway in Human Bladder Cancer Cells.

Bladder cancer is a common malignancy worldwide. However, there is still no effective therapy for bladder cancer. In this study, we investigated the cytotoxic effects of cantharidin [a natural toxin produced (pure compound) from Chinese blister beetles (Mylabrisphalerata or Mylabriscichorii) and Spanish flies (Cantharis vesicatoria)] in human bladder cancer cell lines (including: T24 and RT4 cells). Treatment of human bladder cancer cells with cantharidin significantly decreased cell viability. The increase in the expressions of caspase-3 activity and cleaved form of caspase-9/-7/-3 were also increased in cantharidin-treated T24 cells. Furthermore, cantharidin increased the levels of phospho-eIF2α and Grp78 and decreased the protein expression of procaspase-12, which was accompanied by the increase in calpain activity in T24 cells. Cantharidin was capable of increasing the intracellular Ca (2+) and the phosphorylation of protein kinase C (PKC) in T24 cells. The addition of BAPTA/AM (a Ca (2+) chelator) and RO320432 (a selective cell-permeable PKC inhibitor) effectively reversed the increase in caspase-3 and calpain activity, the phosphorylation levels of PKC and eIF2α and Grp78 protein expression, and the decrease in procaspase-12 expression induced by cantharidin. Importantly, cantharidin significantly decreased the tumor volume (a dramatic 71% reduction after 21 days of treatment) in nude mice xenografted with T24 cells. Taken together, these results indicate cantharidin induced human bladder cancer cell apoptosis through a calcium/PKC-regulated ER stress pathway. These findings suggest that cantharidin may be a novel and potential anticancer agent targeting on bladder cancer cells.

Remove or not, that is the question: A case report on carotid artery cannulation during indwelling venous hemodialysis catheter.

A 58-year-old woman visited the emergency department for acute occlusion of arteriovenous fistula. One session of hemodialysis was scheduled via temporary venous hemodialysis catheter before thrombectomy. Unfortunately, neck arterial cannulation was discovered after complete placement of catheter. The catheter was removed immediately but bleeding could not be stopped. Pseudoaneurysm over the right carotid artery was proved by angiography and repaired by graft stent. Arterial cannulation during venous hemodialysis catheter insertion is a rare but serious complication and there is no standard response recommended. Immediate removal of the misplaced hemodialysis catheter might not be the best choice. We suggest to leave the misplaced catheter in artery until further intervention in consideration of complications and repair access. Every hemodialysis center should standardize responses to arterial cannulation during venous hemodialysis catheter indwelling, especially carotid puncture happens, according to the medical facility.

Chloroacetic acid triggers apoptosis in neuronal cells via a reactive oxygen species-induced endoplasmic reticulum stress signaling pathway.

Chloroacetic acid (CA), a chlorinated analog of acetic acid and an environmental toxin that is more toxic than acetic, dichloroacetic, or trichloroacetic acids, is widely used in chemical industries. Furthermore, CA has been found to be the major disinfection by-products (DBPs) of drinking water. CA has been reported to be highly corrosive and to induce severe tissue injuries (including nervous system) that lead to death in mammals. However, the effects and underlying mechanisms of CA-induced neurotoxicity remain unknown. In the present study, we found that CA (0.5-2.0 mM) significantly increased LDH release, decreased the number of viable cells (cytotoxicity) and induced apoptotic events (including: increases in the numbers of apoptotic cells, the membrane externalization of phosphatidylserine (PS), and caspase-3/-7 activity) in Neuro-2a cells. CA (1.5 mM; the approximate to LD50) also triggered ER stress, which was identified by monitoring several key molecules that are involved in the unfolded protein responses (including the increase in the expressions of p-PERK, p-IRE-1, p-eIF2α, ATF-4, ATF-6, CHOP, XBP-1, GRP 78, GRP 94, and caspase-12) and calpain activity. Transfection of GRP 78- and GRP 94-specific si-RNA effectively abrogated CA-induced cytotoxicity, caspase-3/-7 and caspase-12 activity, and GRP 78 and GRP 94 expression in Neuro-2a cells. Additionally, pretreatment with 2.5 mM N-acetylcysteine (NAC; a glutathione (GSH) precursor) dramatically suppressed the increase in lipid peroxidation, cytotoxicity, apoptotic events, calpain and caspase-12 activity, and ER stress-related molecules in CA-exposed cells. Taken together, these results suggest that the higher concentration of CA exerts its cytotoxic effects in neuronal cells by triggering apoptosis via a ROS-induced ER stress signaling pathway.

Trace analysis of methylated and hydroxymethylated cytosines in DNA by isotope-dilution LC-MS/MS: first evidence of DNA methylation in Caenorhabditis elegans.

From 1986 to the present, the popular research model organism Caenorhabditis elegans has been thought to completely lack DNA methylation and seems to have lost DNA methylation enzymes from its genomes. In the present study, we report the development of a sensitive and selective assay based on LC-MS/MS to simultaneously measure 5-methyl-2'-deoxycytidine (5-mdC) and 5-hydroxymethyl-2'-deoxycytidine (5-hmdC) in DNA hydrolysates. With the use of isotope internal standards ([2H3]5-mdC and [2H3]5-hmdC) and online solid-phase extraction, the detection limits of 5-mdC and 5-hmdC were estimated to be 0.01 and 0.02 pg respectively, which correspond to a 0.000006% and 0.00001% methylation and hydroxymethylation level. This method was applied to investigate whether DNA methylation/hydroxymethylation exists in C. elegans. The present study for the first time demonstrates that 5-mdC is present in C. elegans genomic DNA (0.0019-0.0033% of cytosine methylated) using LC-MS/MS, whereas another epigenetic modification, 5-hmdC, is not detectable. Furthermore, we found that C. elegans DNA was hypo- or hyper-methylated in a dose-dependent manner by the DNA methyltransferase (DNMT)-inhibiting drug decitabine (5-aza-2'-deoxycytidine) or cadmium respectively. Our data support the possible existence of an active DNA-methylation mechanism in C. elegans, in which unidentified DNMTs could be involved. The present study highlights the importance of re-evaluating the evolutionary conservation of DNA-methylation machinery in nematodes which were traditionally considered to lack functional DNA methylation.