Gambogic acid synergistically potentiates cisplatin-induced apoptosis in non-small-cell lung cancer through suppressing NF-κB and MAPK/HO-1 signalling

Background:

Gambogic acid (GA) has been reported to have potent anticancer activity and is authorised to be tested in phase II clinical trials for treatment of non-small-cell lung cancer (NSCLC). The present study aims to investigate whether GA would be synergistic with cisplatin (CDDP) against the NSCLC.

Methods:

1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), combination index (CI) isobologram, western blot, quantitative PCR, flow cytometry, electrophoretic mobility shift assay, xenograft tumour models and terminal deoxynucleotide transferase-mediated dUTP nick-end labelling analysis were used in this study.

Results:

The cell viability results showed that sequential CDDP-GA treatment resulted in a strong synergistic action in A549, NCI-H460, and NCI-H1299 cell lines, whereas the reverse sequence and simultaneous treatments led to a slight synergistic or additive action. Increased sub-G1 phase cells and enhanced PARP cleavage demonstrated that the sequence of CDDP-GA treatment markedly increased apoptosis in comparison with other treatments. Furthermore, the sequential combination could enhance the activation of caspase-3, -8, and 9, increase the expression of Fas and Bax, and decrease the expression of Bcl-2, survivin and X-inhibitor of apoptosis protein (X-IAP) in A549 and NCI-H460 cell lines. In addition, increased apoptosis was correlated with enhanced reactive oxygen species generation. Importantly, it was found that, followed by CDDP treatment, GA could inhibit NF-κB and mitogen-activated protein kinase (MAPK)/heme oxygenase-1 (HO-1) signalling pathways, which have been validated to reduce ROS release and confer CDDP resistance. The roles of NF-κB and MAPK pathways were further confirmed by using specific inhibitors, which significantly increased ROS release and apoptosis induced by the sequential combination of CDDP and GA. Moreover, our results indicated that the combination of CDDP and GA exerted increased antitumour effects on A549 xenograft models through inhibiting NF-κB, HO-1, and subsequently inducing apoptosis.

Conclusion:

Gambogic acid sensitises lung cancer cells to CDDP in vitro and in vivo in NSCLC through inactivation of NF-κB and MAPK/HO-1 signalling pathways, providing a rationale for the combined use of CDDP and GA in lung cancer chemotherapy.

Biomimetic coating of magnesium alloy for enhanced corrosion resistance and calcium phosphate deposition

Degradable metals have been suggested as biomaterials with revolutionary potential for bone-related therapies. Of these candidate metals, magnesium alloys appear to be particularly attractive candidates because of their non-toxicity and outstanding mechanical properties. Despite their having been widely studied as orthopedic implants for bone replacement/regeneration, their undesirably rapid corrosion rate under physiological conditions has limited their actual clinical application. This study reports the use of a novel biomimetic peptide coating for Mg alloys to improve the alloy corrosion resistance. A 3DSS biomimetic peptide is designed based on the highly acidic, bioactive bone and dentin extracellular matrix protein, phosphophoryn. Surface characterization techniques (scanning electron microscopy, energy dispersive X-ray spectroscopy and diffuse-reflectance infrared spectroscopy) confirmed the feasibility of coating the biomimetic 3DSS peptide onto Mg alloy AZ31B. The 3DSS peptide was also used as a template for calcium phosphate deposition on the surface of the alloy. The 3DSS biomimetic peptide coating presented a protective role of AZ31B in both hydrogen evolution and electrochemical corrosion tests.

Molecular characterization of the pseudorabies virus UL2 gene

A 948-bp sequence of the UL2 gene was amplified from the pseudorabies virus (PRV) Becker strain genome using polymerase chain reaction, and the gene identity was confirmed through further cloning and sequencing. Bioinformatic analysis indicated that the PRV UL2 gene encodes a putative polypeptide with 315-amino acid residues. Its encoding protein, designated UL2, has a conserved uracil-DNA glycosylase (UDG)_F1 domain, which is closely related to the herpesvirus UDG family and is highly conserved among its counterparts encoded by UDG genes. Multiple nucleic acid and amino acid sequence alignments suggested that the product of PRV UL2 has a relatively higher homology with UL2-like proteins of Alphaherpesvirinae than that of other subfamilies of Herpesviridae. In addition, phylogenetic analysis showed that PRV UL2 had a close evolutionary relationship with members of Alphaherpesvirinae, especially members of the genus Varicellovirus of bovine herpesvirus 1 and bovine herpesvirus 5. Antigen prediction indicated the presence of several potential B-cell epitopes in PRV UL2. In addition, secondary structure and 3-dimensional structure prediction revealed that PRV UL2 consisted predominantly of an α-helix. Taken together, these results provide molecular biological insight for the further study of the function and mechanism of UL2 during PRV infection.

People who live in a cold climate: thermal adaptation differences based on availability of heating

Are there differences in thermal adaptation to cold indoor environments between people who are used to living in heating and non-heating regions in China? To answer this question, we measured thermal perceptions and physiological responses of young men from Beijing (where there are indoor space heating facilities in winter) and Shanghai (where there are not indoor space heating facilities in winter) during exposures to cold. Subjects were exposed to 12°C, 14°C, 16°C, 18°C, 20°C for 1 h. Subjects from Beijing complained of greater cold discomfort and demonstrated poorer physiological acclimatization to cold indoor environments than those from Shanghai. These findings indicate that people's chronic indoor thermal experience might be an important determinant of thermal adaptation.

Radial and translational oscillations of an acoustically levitated bubble in aqueous ethanol solutions

The radial and translational oscillations of a single cavitation bubble in a standing ultrasound wave were investigated experimentally at various driving acoustic pressures for aqueous ethanol solutions with different bulk molar fractions of ethanol range of 0-1.3 × 10(-3). The results show that both the lower and upper stability thresholds of the acoustic driving pressure decreased as the concentration of ethanol was increased. At a given driving pressure the ambient and maximum bubble sizes increased with increasing ethanol concentration. In addition, as the ethanol was increased, the sonoluminescence intensity decreased while the bubble dynamics remained largely unchanged. The translational oscillation of the levitated bubble, however, became increasingly violent with increasing ethanol concentration. The displacement of the bubble reached 0.7 mm at the highest concentration studied (1.3 × 10(-3)) and the maximum bubble size was found to change as the bubble jumped up and down. This bubble translation may be responsible for the decrease of the acoustic driving pressure threshold and suggests that repetitive injection of ethanol molecules into the bubble takes place. These results may account for the different sensitivities of single bubble and multi-bubble sonoluminescence to the presence of volatile additives.

Perceived parenting and risk for major depression in Chinese women

BACKGROUND

In Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?

METHOD

Received parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.

RESULTS

Factor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.

CONCLUSIONS

Although the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.

Recent advances in the field of 16-membered macrolide antibiotics

The continuing emergence of bacterial resistance has provided an incentive for recent intensified research on macrolide antibiotics. Belonging to the macrolide family, 16-membered macrolides also experience a renewed interest in further exploration. The medicinal potential of 16-membered macrolides in search for new antibacterials stems from some advantages over 14-membered macrolides, such as gastrointestinal tolerability, structural flexibility, and lack of inducible resistance. Thus, compared with abundant articles on various 14-membered macrolide derivatives in the literature, this review will highlight some representative 16-membered macrolide antibiotics and their recently discovered analogs. Furthermore, the action and resistance mechanisms of 16-membered macrolide antibiotics will be elucidated as well to assist the drug design.

A comparison of the thermal adaptability of people accustomed to air-conditioned environments and naturally ventilated environments

It has been reported previously that people who are acclimated to naturally ventilated (NV) environments respond to hot and warm environments differently than people who are acclimated to air-conditioned (AC) environments. However, it is not clear whether physiological acclimatization contributes to this discrepancy. To study whether living and working in NV or AC environments for long periods of time can lead to different types of physiological acclimatization, and whether physiological acclimatization has an important influence on people's responses of thermal comfort, measurements of physiological reactions (including skin temperature, sweat rate, heart rate variability, and heat stress protein 70) and thermal comfort responses were conducted in a 'heat shock' environment (climate chamber) with 20 people (10 in the NV group and 10 in the AC group). The results showed that the NV group had a significantly stronger capacity for physiological regulation to the heat shock than the AC group. In other words, the NV group did not feel as hot and uncomfortable as the AC group did. These results strongly indicate that living and working in indoor thermal environments for long periods of time affects people's physiological acclimatization. Also, it appears that long-term exposure to stable AC environments may weaken people's thermal adaptability.

PRACTICAL IMPLICATIONS

This study examined the psychological and physiological differences of thermal adaptability of people used to air-conditioned environments and naturally ventilated environments. The results suggested that long-term exposure to stable air-conditioned environments may weaken people's thermal adaptability. Therefore, it might be advantageous for people to spend less time in static air-conditioned environments; this is not only because of its possible deleterious impact on people's physiological adaptability, but also because the air-conditioners' high-energy consumption will contribute to the effects of global warming.

Liver X receptor activation attenuates inflammatory response and protects cholinergic neurons in APP/PS1 transgenic mice

Alzheimer's disease (AD) is associated with beta-amyloid deposition, glial activation, and increased levels of the cytokines, as well as cholinergic dysfunction. Liver X receptor (LXR) has been found to inhibit the expression of pro-inflammatory genes. However, the effects of LXR activation on inflammatory response and on cholinergic system in AD are not yet clear. The present results revealed that LXR activation markedly attenuated several inflammatory markers and decreased microglial activation and reactive astrocytes in amyloid precursor protein (APP)/PS1 transgenic mice. Additionally, LXR activation significantly increased the number of cholinergic neurons in the medial septal regions and the basal nucleus of Meynert (NBM), and attenuated cognitive impairment. Furthermore, we observed that LXR activation inhibited the production of COX-2 and iNOS from Aβ(25-35)-induced microglia. LXR activation and nuclear factor kappa B (NF-κB) inhibitor PDTC both attenuated Aβ(25-35) induction of NF-κB activation. These results suggest that LXR agonists suppress the production of pro-inflammatory molecules, at least in part, by modulating NF-κB-signaling pathway. Collectively, these studies suggest that LXR agonists may have therapeutic significance in AD.

Effect of alcohol on single-bubble sonoluminescence

The driving parametric regions in frequency-amplitude space and the optimal parameters for single-bubble sonoluminescence (SBSL) in alcohol aqueous solutions are studied systematically by taking measurements of the spectrum and bubble dynamics. The experimental results show that with an increase in alcohol concentration, the region shrinks and shifts. The optimized parameters differ for alcohol solutions having different concentrations, and SBSL driven by fixed parameters dims quickly and is even destroyed immediately with the addition of a small amount of alcohol to pure water. Furthermore, it is seen that the intensity of optimized SBSL decreases as the alcohol concentration increases. The corresponding measurements of the dynamics of the optimized SBSL bubble show that the maximum bubble radius at an alcohol concentration of 1.04 mM is only half that for pure water. Meanwhile, the optimized driving amplitude acquired by direct measurement and that obtained by fitting the radius-time curves with the Rayleigh-Plesset equation both decrease by 12% in the same comparison. Therefore, a decrease in the driving acoustic pressure may be an important reason for the decrease in the optimized SBSL intensity, which should help clarify SBSL mechanisms in alcohol aqueous solutions.

Microbubble sizing and shell characterization using flow cytometry

Experiments were performed to size, count, and obtain shell parameters for individual ultrasound contrast microbubbles using a modified flow cytometer. Light scattering was modeled using Mie theory, and applied to calibration beads to calibrate the system. The size distribution and population were measured directly from the flow cytometer. The shell parameters (shear modulus and shear viscosity) were quantified at different acoustic pressures (from 95 to 333 kPa) by fitting microbubble response data to a bubble dynamics model. The size distribution of the contrast agent microbubbles is consistent with manufacturer specifications. The shell shear viscosity increases with increasing equilibrium microbubble size, and decreases with increasing shear rate. The observed trends are independent of driving pressure amplitude. The shell elasticity does not vary with microbubble size. The results suggest that a modified flow cytometer can be an effective tool to characterize the physical properties of microbubbles, including size distribution, population, and shell parameters.

Immunological features in patients with pneumonitis due to influenza A H1N1 infection

BACKGROUND

Pneumonitis induced by pandemic influenza A H1N1 has a potential to cause respiratory failure, which is a risk factor for death. The underlying immunopathological mechanisms, however, have not yet been fully elucidated.

PATIENTS AND METHODS

We investigated changes in plasma cytokines, T cell subsets, and C-reactive protein (CRP) in 16 hospitalized patients with pneumonia caused by 2009 H1N1 influenza infection. The patients were classified into a severe disease group and a mild disease group according to PaO2.

RESULTS

Cytokine profiles showed no changes in interferon gamma (IFN-gamma), interleukin 6 (IL-6), IL-8, or transforming necrosis factor alpha (TNF-alpha) levels throughout the observation period. Transforming growth factor beta (TGF-beta1) was overproduced in the severe group but not in the mild group. Accordingly, we also found some signs of pulmonary fibrosis during the recovery period. Elevated CRP levels and lymphopenia were common in both the severe and the mild group. After treatment, there was a significant elevation in lymphocytes in both groups, but a significant decrease in CRP in the mild group. Lymphocyte counts and CRP levels rapidly recovered to normal levels in all survivors posttreatment; otherwise it seemed to be related to poor prognosis.

CONCLUSIONS

Serial measurements of cytokines showed that only TGF-beta1 was overproduced, possibly in relation to the early use of corticosteroids, which may have downregulated immune responses to H1N1 infection. Pretreatment TGF-beta1 plasma concentrations and absolute lymphocyte counts were independent predictors of severity. However, the role of elevated TGF-beta1 in H1N1 infection-associated pulmonary fibrosis requires further investigation.

Increased levels of soluble vascular endothelial cadherin are associated with poor outcome in severe sepsis

Endothelial cells are thought to play a key role in sepsis pathogenesis: vascular endothelial damage occurs in severe sepsis and multiple organ dysfunction. Soluble vascular endothelial cadherin (VE-cadherin) levels were investigated in a prospective study involving 28 consecutive critically ill patients with or without severe sepsis who were admitted to surgical intensive care; 13 healthy age-matched volunteers were included as controls. Soluble VE-cadherin levels increased significantly in patients with severe sepsis compared with ill patients without severe sepsis and healthy controls. There was a significant linear correlation between soluble VE-cadherin levels and illness severity scores. Soluble VE-cadherin levels were significantly higher in patients who died compared with survivors. In vitro cell culture showed that serum from patients with severe sepsis greatly decreased VE-cadherin staining at intercellular junctions and total VE-cadherin expression in human umbilical cord vein endothelial cells. These findings suggest that endothelial cells play an important role in the poor outcome of patients with severe sepsis.