The mechanism of carvacrol-evoked [Ca2+]i rises and non-Ca2+-triggered cell death in OC2 human oral cancer cells

Carvacrol is one of the main substances of essential oil which triggers intracellular Ca²⁺ mobilization and causes cytotoxicity in diverse cell models. However, the mechanism of carvacrol-induced Ca²⁺ movement and cytotoxicity is not fully understood. This study examined the effect of carvacrol on cytosolic free Ca²⁺ concentrations ([Ca²⁺]_i), cell viability and apoptosis in OC2 human oral cancer cells. Carvacrol induced a [Ca²⁺]_i rise and the signal was reduced by removal of extracellular Ca²⁺. Carvacrol-induced Ca²⁺ entry was not altered by store-operated Ca²⁺ channel inhibitors and protein kinase C (PKC) activator, but was inhibited by a PKC inhibitor. In Ca²⁺ -free medium, treatment with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) inhibited carvacrol-induced [Ca²⁺]_i rise. Conversely, incubation with carvacrol inhibited TG or BHQ-induced [Ca²⁺]_i rise. Inhibition of phospholipase C (PLC) with U73122 abolished carvacrol-induced [Ca²⁺]_i rise. Carvacrol decreased cell viability, which was not reversed when cytosolic Ca²⁺ was chelated with BAPTA-AM (1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid-acetoxymethyl ester). Carvacrol-induced apoptosis and activation of reactive oxygen species (ROS) and caspase-3. Together, carvacrol induced a [Ca²⁺]_i rise by inducing PLC-dependent Ca²⁺ release from the endoplasmic reticulum and Ca²⁺ entry via PKC-sensitive, non store-operated Ca²⁺ channels. Carvacrol-induced ROS- and caspase-3-associated apoptosis.     

Chloroacetic acid induced neuronal cells death through oxidative stress-mediated p38-MAPK activation pathway regulated mitochondria-dependent apoptotic signals

Chloroacetic acid (CA), a toxic chlorinated analog of acetic acid, is widely used in chemical industries as an herbicide, detergent, and disinfectant, and chemical intermediates that are formed during the synthesis of various products. In addition, CA has been found as a by-product of chlorination disinfection of drinking water. However, there is little known about neurotoxic injuries of CA on the mammalian, the toxic effects and molecular mechanisms of CA-induced neuronal cell injury are mostly unknown. In this study, we examined the cytotoxicity of CA on cultured Neuro-2a cells and investigated the possible mechanisms of CA-induced neurotoxicity. Treatment of Neuro-2a cells with CA significantly reduced the number of viable cells (in a dose-dependent manner with a range from 0.1 to 3 mM), increased the generation of ROS, and reduced the intracellular levels of glutathione depletion. CA also increased the number of sub-G1 hypodiploid cells; increased mitochondrial dysfunction (loss of MMP, cytochrome c release, and accompanied by Bcl-2 and Mcl-1 down-regulation and Bax up-regulation), and activated the caspase cascades activations, which displayed features of mitochondria-dependent apoptosis pathway. These CA-induced apoptosis-related signals were markedly prevented by the antioxidant N-acetylcysteine (NAC). Moreover, CA activated the JNK and p38-MAPK pathways, but did not that ERK1/2 pathway, in treated Neuro-2a cells. Pretreatment with NAC and specific p38-MAPK inhibitor (SB203580), but not JNK inhibitor (SP600125) effectively abrogated the phosphorylation of p38-MAPK and attenuated the apoptotic signals (including: decrease in cytotoxicity, caspase-3/-7 activation, the cytosolic cytochrome c release, and the reversed alteration of Bcl-2 and Bax mRNA) in CA-treated Neuro-2a cells. Taken together, these data suggest that oxidative stress-induced p38-MAPK activated pathway-regulated mitochondria-dependent apoptosis plays an important role in CA-caused neuronal cell death.     

Pulmonary embolectomy in high-risk acute pulmonary embolism: The effectiveness of a comprehensive therapeutic algorithm including extracorporeal life support

Objectives

To investigate the effectiveness of a comprehensive therapeutic algorithm including extracorporeal life support (ECLS) in high-risk acute pulmonary embolism (aPE) treated with pulmonary embolectomy.

Materials and methods

This retrospective study included 25 consecutive patients of aPE treated with pulmonary embolectomy in a single institution between June 2005 and July 2012. All patients had high-risk aPE identified by computed tomographic angiography and were not suitable for thrombolytic therapy. High-risk aPE here was defined as aPE with (1) hemodynamic instability, (2) a pulmonary artery obstruction index (PAOI) ≥ 0.5, (3) a diameter ratio of right ventricle-to-left ventricle (RV-to-LV) ≥ 1.0, or (4) right heart thrombi. Once the eligibility was confirmed, a 3-staged therapeutic algorithm was adopted to perform an aggressive preoperative resuscitation, an expeditious pulmonary embolectomy with multidisciplinary postoperative care, and a thorough surveillance for recurrence.

Results

Among the 25 patients, 24 had a PAOI ≥ 0.5 and 23 had a RV-to-LV diameter ratio ≥ 1.0. Four patients had right heart thrombi. Sixteen patients developed preoperative instability requiring inotropic and/or mechanical support. Eight in the 16 had a preoperative cardiac arrest (CA) and six of these were bridged to surgery on ECLS. Three in the 6 patients weaned ECLS after surgery and survived to discharge. The overall in-hospital mortality was 20% (n = 5). A preoperative CA (Odds ratio [OR]: 16, 95% confidence interval [CI]: 1.4–185.4, p = 0.027, c-index: 0.80) and a postoperative requirement of ECLS (OR: 36, 95% CI: 2.1–501.3, p = 0.008, c-index: 0.85) was the pre- and postoperative predictor of in-hospital mortality. No late deaths or re-admission for recurrence were found during a median follow-up of 19 months (interquartile range: 8–29).

Conclusion

Pulmonary embolectomy was an effective intervention of high-risk aPE. However, the occurrence of preoperative CA still carried a high mortality in spite of the assistance of ECLS.     

Mortality in Emergency Department Sepsis score as a prognostic indicator in patients with pyogenic liver abscess

Objectives

The purpose of this study was to explore the predictor index of mortality in patients with pyogenic liver abscess (PLA).

Methods

We performed a retrospective review that enrolled 431 patients 18 years and older hospitalized due to PLA between January 2005 and December 2010. Clinical characteristics, laboratory results, treatments, and outcomes retrieved from medical records were analyzed. Multiple logistic regression and receiver operating characteristic curve analyses were performed.

Results

The mean age of the 431 patients identified with PLA was 56.9 ± 15.0 years. The mean Mortality in Emergency Department Sepsis (MEDS) score on admission was 4.8 ± 4.1 (range, 0-17). During hospitalization, 94 patients (22%) required intensive care. Of the 431 patients, 63 died, yielding a 15% case fatality rate. Multivariate analysis revealed that higher MEDS scores on admission (P < .0001) and the presence of underlying malignancy (P = .006), multiple abscesses (P = .001), anaerobic infections (P < .0001), hyperbilirubinemia (P < .0001), and higher serum creatinine levels (P < .0001) were significantly associated with PLA mortality. The estimated area under the receiver operating characteristic curve for MEDS in predicting PLA mortality was 0.829 (95% confidence interval, 0.791-0.864; P < .0001). The optimal cutoff MEDS value of 7 or higher had a sensitivity of 76% sensitivity and a specificity of 81%, with a 10.7-fold PLA mortality risk (P < .0001) and a 26.2-fold intensive care unit admission risk (P < .0001).

Conclusions

The MEDS scores on admission represent a significant prognostic indicator for patients with PLA.     

Electrostatic immobilization of DNA polyplexes on small intestinal submucosa for tissue substrate-mediated transfection

Naturally occurring extracellular matrices (ECMs) such as small intestinal submucosa (SIS) have received significant attention for their therapeutic applications in tissue repair and regeneration. However, there have been no reports exploring the electrostatic properties of naturally occurring ECMs as a means to control transgene delivery. In the present study, we electrostatically adsorbed DNA polyplexes onto SIS for transfection upon cellular adhesion. To associate polyplexes with SIS, we first used a streaming potential method to characterize the surface charge of SIS and obtained a negative zeta potential at neutral pH, which can be attributed to the abundant glycosaminoglycan (GAG) content in SIS. We next prepared cationic polyethylenimine (PEI)/DNA polyplexes to associate with the negatively charged SIS for conjugation. Using the Cy(TM)3 dye-labeled control DNA as the reporter, we visualized the adsorption of PEI/DNA polyplexes at the SIS surface. Using luciferase, green fluorescent protein and beta-galactosidase as reporter proteins, we showed that the adsorbed PEI/DNA polyplexes were active and capable of carrying out transfection upon cellular adhesion, indicating that the electrostatic binding of polyplexes with SIS was reversible. In addition, the SIS-mediated transfection was contact-dependent: separation of SIS from the target cells via a 0.5 mm porous polyester membrane significantly reduced the efficiency of transfection in comparison to a direct seeding of cells onto SIS. We conclude that electrostatic immobilization of PEI/DNA polyplexes on SIS is capable of initiating efficient transgene delivery, which can be a useful tool in developing localized gene transfer.     

Disparities and survival in newly diagnosed gastric cancer in Hispanic patients in the United States: a propensity score matched analysis

BackgroundThe burden of gastric cancer involving Hispanic patients in the United States is growing as both the population and the incidence of gastric cancer in this group increases. This burden is compounded by presentation with advanced disease and socioeconomic challenges shaping cancer care. We sought to describe the demographics, socioeconomic factors, treatment, and survival experience of Hispanic patients with gastric adenocarcinoma.MethodsPatients with gastric adenocarcinoma diagnosed between 2004 and 2015 (n=90,737) in the National Cancer Database were retrospectively identified. Patients of Hispanic ethnicity were compared against non-Hispanic white patients. Surgical cohort was further analyzed, and 1:1 propensity score matching was used to balance covariates between Hispanic and non-Hispanic white surgical patients. Survival was compared using Kaplan-Meier method. Cox regression was used to determine prognostic factors for survival.ResultsCompared to non-Hispanic white patients, Hispanic patients are more likely to be younger, female, and healthier. They were more likely to be uninsured, reside in poorer neighborhoods and reside in areas with lower rates of education. Hispanic patients were more likely to live in a metropolitan area, travel shorter distances for healthcare, and receive treatment at an academic and high volume centers. Hispanic patients were more likely to have higher stage disease presentation, higher grade tumors, lymphovascular invasion, and poorly cohesive adenocarcinoma. Hispanic patients were more likely to receive surgery, but less likely to receive adjuvant therapy. In Cox regression of all patients, unmatched surgical patients, and matched surgical patients, Hispanic ethnicity was an independent prognostic factor of improved survival.ConclusionsHispanic patients with gastric adenocarcinoma present with several unfavorable clinicopathologic and socioeconomic factors. Paradoxically, these patients demonstrate improved survival. Further study is warranted to characterize disease biology in this population.