Add-on effect of clarithromycin to oral steroids as post- operative therapy for chronic rhinosinusitis with nasal polyps: a randomised controlled trial.

BACKGROUND: Evidence is lacking regarding the efficacy of macrolides and oral corticosteroids in chronic rhinosinusitis with nasal polyps (CRSwNP) after endoscopic sinus surgery (ESS). Therefore, we examined the benefits of adding clarithromycin to oral pred- nisolone as post-ESS medical therapy in patients with CRSwNP. METHODS: In this randomised, double-blind, placebo-controlled trial, patients were enrolled and allocated to three study groups receiving different post-ESS medical therapies: group A (placebo for 14 weeks), group B (oral prednisolone [15 mg twice daily] for 2 weeks, followed by placebo for 12 weeks), and group C (oral prednisolone [15 mg twice daily] for 2 weeks, followed by clari- thromycin [500 mg daily] for 12 weeks). All enrolled patients received the perioperative care following a routine protocol, which included oral amoxicillin/clavulanate, and intranasal corticosteroid spray. The baseline and post-operative visual analogue scale (VAS) scores, Sino-nasal Outcome Test (SNOT-22) scores, and Lund-Kennedy endoscopy scores (LKES) were determined as the primary outcomes. RESULTS: One hundred twenty-six patients who received ESS for bilateral CRSwNP were randomised into group A (n=43), B (n=42), or C (n=41). Compared to groups A and B, group C showed greater VAS and SNOT-22 score improvement at 12 weeks after ESS. Group C showed significantly better LKES than did groups A and B at 8, 12, and 24 weeks after ESS. On stratifying the LKES results according to the presence/absence of tissue eosinophilia, greater add-on effects of clarithromycin were observed in the patient subgroup without tissue eosinophilia. CONCLUSIONS: Adding low-dose clarithromycin to oral corticosteroids as post-ESS therapy was well tolerated and showed benefi- cial subjective and objective outcomes in patients with CRSwNP, especially those without tissue eosinophilia.

Phosphorylation of glycogen synthase kinase-3ß in metabolically abnormal obesity affects immune stimulation-induced cytokine production.

BACKGROUND: Obesity is a severe health problem worldwide, which leads to multiple comorbidities including type 2 diabetes mellitus and cardiovascular diseases. Inflammation has been found to be an important characteristic of adipose tissue in obese subjects. However, obesity is also associated with compromised immune responses to infections and the impact of obesity on immune function has not been fully understood. SUBJECTS/METHODS: To clarify the role of obesity in the immune responses, we investigated the Toll-like receptor (TLR)-induced cytokine secretion by leukocytes from obese and lean subjects. We also investigated the relationship between insulin-induced intracellular signaling and cytokine production using peripheral blood mononuclear cells (PBMCs) and a monocytic cell line THP-1. RESULTS: We found decreased TLR-induced interferon-γ, interleukin-6 (IL-6) and tumor necrosis factor-α secretions and elevated IL-10 secretion by leukocytes from obese subjects when compared with lean controls. PBMCs from obese subjects showed enhanced basal Akt and glycogen synthase kinase-3ß (GSK-3ß) phosphorylation, which did not further increase with insulin and lipopolysaccharide (LPS) stimulation. We also found that LPS-induced IκBα degradation was inhibited in PBMCs from obese subjects. By using THP-1 cells with GSK-3ß knockdown or cells treated with hyperinsulinemic and high-fatty acid conditions, we found that LPS-induced nuclear factor κB (NF-κB) activation was inhibited and cyclic adenosine monophosphate response element-binding protein (CREB) activation was enhanced. CONCLUSIONS: These findings indicate that GSK-3ß is important in the regulation of NF-κB and CREB activation in leukocytes under the metabolic condition of obesity. Our study revealed a key mechanism through which metabolic abnormalities compromise leukocyte functions in people with obesity.

Transcriptomes of the major human pancreatic cell types.

AIMS/HYPOTHESIS: We sought to determine the mRNA transcriptome of all major human pancreatic endocrine and exocrine cell subtypes, including human alpha, beta, duct and acinar cells. In addition, we identified the cell type-specific distribution of transcription factors, signalling ligands and their receptors. METHODS: Islet samples from healthy human donors were enzymatically dispersed to single cells and labelled with cell type-specific surface-reactive antibodies. Live endocrine and exocrine cell subpopulations were isolated by FACS and gene expression analyses were performed using microarray analysis and quantitative RT-PCR. Computational tools were used to evaluate receptor-ligand representation in these populations. RESULTS: Analysis of the transcriptomes of alpha, beta, large duct, small duct and acinar cells revealed previously unrecognised gene expression patterns in these cell types, including transcriptional regulators HOPX and HDAC9 in the human beta cell population. The abundance of some regulatory proteins was different from that reported in mouse tissue. For example, v-maf musculoaponeurotic fibrosarcoma oncogene homologue B (avian) (MAFB) was detected at equal levels in adult human alpha and beta cells, but is absent from adult mouse beta cells. Analysis of ligand-receptor interactions suggested that EPH receptor-ephrin communication between exocrine and endocrine cells contributes to pancreatic function. CONCLUSIONS/INTERPRETATION: This is the first comprehensive analysis of the transcriptomes of human exocrine and endocrine pancreatic cell types-including beta cells-and provides a useful resource for diabetes research. In addition, paracrine signalling pathways within the pancreas are shown. These results will help guide efforts to specify human beta cell fate by embryonic stem cell or induced pluripotent stem cell differentiation or genetic reprogramming.

Foot pressure and center of pressure in athletes with ankle instability during lateral shuffling and running gait.

This study evaluates foot pressure and center of pressure (COP) patterns in individuals with ankle instability during running and lateral shuffling. Eleven participants with ankle instability (AI) and 11 normal subjects (Normal) performed running and lateral shuffling tasks. The outcome measures were foot progression angle, peak pressure, and displacement of COP during stance phase. During running, the foot progression angle, that is, the angle of foot abduction, was lower in the AI group (Normal: 13.46° ± 4.45°; AI: 8.78° ± 3.91°), and the 1st metatarsal contact pressure (Normal: 0.76 ± 0.47 N/cm(2)·kg; AI: 1.05 ± 0.70 N/cm(2)·kg) and the 3rd metatarsal peak pressure were higher in the AI (Normal: 0.96 ± 0.60 N/cm(2)·kg; AI: 1.54 ± 0.68 N/cm(2)·kg). The medial-lateral (M-L) COP in the late-stance phase of running for the AI group transferred faster from lateral to medial foot than the Normal group. For lateral shuffling, the AI group had greater peak pressure at the 1st (Normal: 0.76 ± 0.67 N/cm(2)·kg; AI: 1.49 ± 1.04 N/cm(2)·kg), 2nd (Normal: 0.57 ± 0.39 N/cm(2)·kg; AI: 0.87 ± 0.68 N/cm(2)·kg), 3rd (Normal: 0.70 ± 0.54 N/cm(2)·kg; AI: 1.42 ± 0.87 N/cm(2)·kg), and 4th (Normal: 0.52 ± 0.38 N/cm(2)·kg; AI: 1.12 ± 0.78 N/cm(2)·kg) metatarsal areas than the Normal group. The M-L COP located more laterally from the early to mid-stance phase in the AI compared with the Normal group. The findings suggest that COP displacement during lateral shuffle may be a factor in ankle instability while the foot progression angle during running may be a compensatory strategy.

In vitro activities of doripenem and other carbapenems against clinically important bacteria isolated in intensive care units: nationwide data from the SMART Programme.

This nationwide surveillance of clinically important bacteria from the intensive care units (ICUs) of major teaching hospitals throughout Taiwan investigated the susceptibilities to doripenem and other comparator carbapenems from September through November 2005. Minimum inhibitory concentrations (MICs) were determined for 1,311 clinical isolates using the broth microdilution method according to Clinical and Laboratory Standards Institute (CLSI) 2005 guidelines. Doripenem showed similar (within four-fold difference of MICs) in vitro activity to meropenem for Enterobacteriaceae and probably comparable activity to meropenem against important nosocomial non-fermentative Gram-negative bacilli (NFGNBs), including Pseudomonas aeruginosa, Acinetobacter baumannii and Burkholderia cepacia. Among the four carbapenems analysed, doripenem and meropenem exhibited better in vitro activity than imipenem or ertapenem against extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli isolates. However, the meropenem MIC(90) against ESBL-producing K. pneumoniae isolates was 2 microg/ml. Besides, doripenem with the MIC(90) of 0.5 microg/ml to Streptococcus pneumoniae possibly suggested its potential therapeutic effect regarding community-acquired pneumonia. Because of the heavy resistance burden in Taiwan, closely monitoring the evolutionary trend of carbapenem susceptibilities against clinically important pathogens is crucial in the future.

Light extraction efficiency enhancement of GaN-based light emitting diodes on n-GaN layer using a SiO2 photonic quasi-crystal overgrowth.

In this paper, GaN-based LEDs with a SiO2 photonic quasi-crystal (PQC) pattern on an n-GaN layer by nano-imprint lithography (NIL) are fabricated and investigated. At a driving current of 20 mA on Transistor Outline (TO)-can package, the better light output power of LED III (d = 1.2 microm) was enhanced by a factor of 1.20. After 1000 h life test (55 degrees C/50 mA) condition, Normalized output power of LED with a SiO2 PQC pattern (LED III (d = 1.2 microm)) on an n-GaN layer only decreased by 5%. This results offer promising potential to enhance the light output power of commercial light-emitting devices using the technique of nano-imprint lithography.

Differential effects of propofol and isoflurane on the activation of T-helper cells in lung cancer patients.

It is suggested that activation and differentiation of T-helper cells are required for peri-operative anti-tumor and anti-infection immunity. The present study aimed to evaluate whether propofol stimulates the activation and differentiation of these cells in patients undergoing pulmonary lobectomy for non-small-cell lung cancer. Thirty patients were randomly allocated to receive propofol or isoflurane throughout surgery. The CD4(+)CD28(+) percentage (p < 0.0001) and the ratio of interferon-gamma:interleukin-4 (p = 0.001) all increased with propofol but showed no change with isoflurane. In contrast, cortisol increased with isoflurane (p < 0.0001) but not with propofol over time (p = 0.06). We conclude that propofol promotes activation and differentiation of peripheral T-helper cells.

An 802.11 n wireless local area network transmission scheme for wireless telemedicine applications.

In this paper, an 802.11 n transmission scheme is proposed for wireless telemedicine applications. IEEE 802.11n standards, a power assignment strategy, space-time block coding (STBC), and an object composition Petri net (OCPN) model are adopted. With the proposed wireless system, G.729 audio bit streams, Joint Photographic Experts Group 2000 (JPEG 2000) clinical images, and Moving Picture Experts Group 4 (MPEG-4) video bit streams achieve a transmission bit error rate (BER) of 10-7, 10-4, and 103 simultaneously. The proposed system meets the requirements prescribed for wireless telemedicine applications. An essential feature of this proposed transmission scheme is that clinical information that requires a high quality of service (QoS) is transmitted at a high power transmission rate with significant error protection. For maximizing resource utilization and minimizing the total transmission power, STBC and adaptive modulation techniques are used in the proposed 802.11 n wireless telemedicine system. Further, low power, direct mapping (DM), low-error protection scheme, and high-level modulation are adopted for messages that can tolerate a high BER. With the proposed transmission scheme, the required reliability of communication can be achieved. Our simulation results have shown that the proposed 802.11 n transmission scheme can be used for developing effective wireless telemedicine systems.

Combining the Capilia TB assay with smear morphology for the identification of Mycobacterium tuberculosis complex.

SETTING: Many hospitals in Taiwan use the fully automated BACTEC Mycobacterial Growth Indicator Tube (MGIT) 960 system to identify mycobacteria in clinical specimens, while the labour-intensive BD ProbeTec ET (CTB) system or biochemical methods are used to identify Mycobacterium tuberculosis complex (MTC) in mycobacterially positive BACTEC cultures. OBJECTIVE: To evaluate whether the Capilia TB assay can be used to replace the BD ProbeTec ET (CTB) system or biochemical methods for identifying MTC in BACTEC cultures. DESIGN: Mycobacterially positive BACTEC cultures were collected and MTC in the cultures was identified using biochemical methods. MTC was identified using serpentine cording in smears, the Capilia TB assay or the BD ProbeTec ET (CTB) system, and the results were compared. RESULTS: Using 233 mycobacterially positive BACTEC cultures, the sensitivity and specificity of identification of the Capilia TB assay were respectively 96.9% and 98.6%, while those of the BD ProbeTec ET (CTB) system were respectively 99.4% and 97.3%. Combining the Capilia TB assay with serpentine cording in smears led to 100% specificity for intersected results and 100% sensitivity for combined results. CONCLUSION: The Capilia TB assay can be used to identify MTC in BACTEC cultures. By combining the assay with serpentine cording in smears, false-positives and -negatives may be reduced.

Combining polymerase chain reaction restriction enzyme analysis with phenotypic characters for mycobacteria identification in Taiwan.

SETTING: Many hospitals use the fully-automated BACTEC 960 Mycobacteria Growth Indicator Tube (MGIT) system and acid-fast staining to detect acid-fast bacilli (AFB) in clinical specimens; however, labour-intensive biochemical methods are used for further mycobacterial species identification. OBJECTIVE: To develop a user-friendly algorithm for mycobacterial species identification from AFB smear-positive BACTEC tubes. DESIGN: AFB smear-positive BACTEC tubes were collected and mycobacteria were isolated and identified by biochemical methods. The tubes were subgrouped by rpoB duplex polymerase chain reaction restriction enzyme analysis (rpoB DPRA). The results were combined with key phenotypic characters of mycobacteria isolated from the tubes to develop a species identification algorithm with 16S rDNA sequencing of the isolate being used as the gold standard method. RESULTS: By rpoB DPRA, 441 AFB smear-positive BACTEC tubes were correctly subgrouped into 100 tubes containing Mycobacterium tuberculosis complex, 335 tubes containing non-tuberculous mycobacteria and six tubes containing both. A species identification algorithm was developed by combining the rpoB DPRA results of the tubes with growth rate, photoreactivity and two biochemical results of mycobacteria recovered from the tubes. CONCLUSION: This user-friendly algorithm can be used for mycobacterial species identification from AFB smear-positive BACTEC tubes.

Nationwide surveillance of antimicrobial resistance among Haemophilus influenzae and Streptococcus pneumoniae in intensive care units in Taiwan.

A nationwide susceptibility surveillance of Streptococcus pneumoniae and Haemophilus influenzae isolates collected from patients treated at the intensive care units (ICUs) of ten Taiwanese major teaching hospitals was conducted from September 2005 through November 2005. High rates of resistance (intermediate/resistant) of S. pneumoniae to penicillin (85% resistance), ceftriaxone (46%/20%), and cefepime (43%/15%) by meningitis criteria, and in contrast, non-susceptibilities (intermediate/resistant) to penicillin (0%/0%), ceftriaxone (20%/0%) and cefepime (15%/0%) by non-meningitis criteria were noted (p values < 0.05) by the Clinical and Laboratory Standards Institute 2008. Resistant rate of S. pneumoniae to azithromycin was also high (63%). S. pneumoniae isolates were significantly more susceptible to ertapenem (87%) than to imipenem (39%) and meropenem (44%) (p values < 0.05). Rates of non-susceptibilities of H. influenzae isolates to ampicillin and cefaclor were high (55% and 45%, respectively). No beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae isolates were found. Imipenem has a notably higher MIC(90) value (8 microg/ml) for H. influenzae than that of the other two carbapenems. Tigecycline showed good in vitro activities against these two respiratory pathogens. High rates of resistance among isolates of S. pneumoniae and H. influenzae continue to exist in the ICUs of Taiwan.

Nationwide surveillance of antimicrobial resistance among Enterobacteriaceae in intensive care units in Taiwan.

To determine the antimicrobial resistance profiles among clinical isolates of Enterobacteriaceae in Taiwanese intensive care units (ICUs), a national surveillance of antibiotic resistance among important Enterobacteriaceae was conducted from September 2005 through November 2005 at the ICUs of ten major teaching hospitals in Taiwan. A total of 574 Enterobacteriaceae isolates recovered from various clinical samples of our ICU patients were submitted for in vitro test. Minimum inhibitory concentrations (MICs) of these isolates to 18 antimicrobial agents were determined by the broth microdilution method. The prevalences of Enterobacteriaceae isolates with phenotypic extended-spectrum beta-lactamase (ESBL) production were 26% in Klebsiella pneumoniae, 16% in Serratia marcescens, 14% in Escherichia coli, and 13% in Proteus mirabilis, in which a significantly rising prevalence of ESBL production among K. pneumoniae was noted (p = 0.002) when compared with a previous Taiwanese survey in 2000. Heterogeneous resistance to various fluoroquinolones was found among our Enterobacteriaceae isolates, except for Enterobacter cloacae. Emergence of ertapenem-resistant isolates of E. coli, K. pneumoniae, E. cloacae, and S. marcescens was noted. Gradually increasing rates of drug-resistant Enterobacteriaceae were noted in Taiwanese ICUs. Periodic surveillance of the evolutionary trend of antimicrobial resistance among ICU isolates is crucial for starting appropriately empirical antimicrobial therapy in the future.

White-light electroluminescence from ZnO nanorods/polyfluorene by solution-based growth.

We report bright white-light electroluminescence (EL) from a diode structure consisting of a ZnO nanorod (NR) and a p-type conducting polymer of poly(fluorine) (PF) fabricated using a hydrothermal method. ZnO NRs are successfully grown on an organic layer of PF using a modified seeding layer. The EL spectrum shows a broad emission band covering the entire visible range from 400 to 800 nm. White-light emission is possible because the ZnO-defect-related emission from the ZnO NR/PF heterostructure is enhanced to become over thousand times stronger than that from the usual ZnO NR structure. This strong green-yellow emission associated with the ZnO defects, combined with the blue PF-related emission, results in the white-light emission. Enhancement of the ZnO-defect emission is caused by the presence of Zn(OH)(2) at the interface between the ZnO NRs and PF. Fourier transform infrared spectroscopy reveals that the absorption peaks at 3441, 3502, and 3574 cm(-1) corresponding to the OH group are formed at the ZnO NR/PF heterostructure, which confirms the enhancement of defect emission from the ZnO NR/PF heterostructure. The processing procedure revealed in this work is a convenient and low-cost way to fabricate ZnO-based white-light-emitting devices.

Jar-opening challenges. Part 1: an apparatus for assessing hand and finger torques and forces in a jar-opening activity.

A simulated jar apparatus was developed to record hand kinetics and torque contribution of a digit during jar-opening activities. The design of the apparatus, namely a jar body and a lid, is similar to a commercial jam jar that is regularly seen in daily living. One six-axis force-torque transducer and a torque cell were mounted inside the jar lid to detect the external force exerted from the digit and fixed on to the jar body to record the overall torque generated by the hand and wrist respectively. The applications of the apparatus were used to test the twisting torque of the hand and to measure the applied forces of the digit, which are both important factors in opening a jar. The contribution of each digit relative to the total twisting torque of the hand could be obtained via the apparatus. The intraclass correlation coefficient of the repeated measurements of the obtained forces and moments for different counterweights was approximately 0.96-1.00, which indicates that the reliability of the measured components of the apparatus is high. The high coefficient of determination (r2 > 0.99) indicates high accuracy of prediction of the measured values with respect to the expected loads. The validation outcomes support the design rationale and actual body part of the simulated jar. In addition, understanding the contribution of a single digit in opening a jar was also achieved via the apparatus and model.

Jar-opening challenges. Part 2: estimating the force-generating capacity of thumb muscles in healthy young adults during jar-opening tasks.

This study discusses the force-generating capacity of thumb muscles during jar-opening tasks using two grip patterns: the power grip and the precision grip. This study develops a three-dimensional biomechanical model of the thumb to predict muscle forces in jar-opening activities based on external forces measured by a custom-designed jar device. Ten healthy subjects participated in the study. Each participant turned a jar lid of 66 mm diameter counterclockwise with maximal effort and preferred speed using both grip patterns. The average normal and tangential forces applied by the thumb to the jar lid show that the normal force is the primary contributive force for opening a jar. This normal force is approximately three times the tangential force. Muscular force-generating capacity measurements show that the major active muscles during a jar-opening activity for both grips include the flexor pollicis longus, flexor pollicis brevis, abductor pollicis brevis, adductor pollicis, and opponens pollicis. The total muscle force ratios for the precision grip and power grip with respect to externally applied forces are 5.6 and 4.7 respectively. These ratios indicate that the power grip pattern produces less muscle force per unit of external applied load. The technique proposed in this study provides a proper apparatus and model for measuring three-dimensional loads and estimating the force-generating capacity of each muscle and tendon of the thumb during jar-opening tasks.

Interferon-alpha-induced serotonin uptake in Jurkat T cells via mitogen-activated protein kinase and transcriptional regulation of the serotonin transporter.

Interferon (IFN)-alpha upregulates serotonin (5-HT) uptake and serotonin transporter (5-HTT) messenger ribonucleic acid (mRNA) expression in immune cells, which implies the mechanism underlying IFN-alpha-induced depression. However, the signal transduction of this effect remains unclear. We investigated whether the effects of IFN-alpha on the functions of 5-HTT were related to mitogen-activated protein kinase (MAPK). By performing Western blotting, real-time reverse transcriptase-polymerase chain reaction and [3H]5-HT labelling, we examined MAPK phosphorylation, 5-HTT mRNA expression and 5-HT uptake in Jurkat T cells. The cells had been cultured for different time periods (1) with IFN-alpha alone and (2) preincubated with either MAPK inhibitors or with the selective serotonin reuptake inhibitor, fluoxetine, and subsequently cultured along with IFN-alpha. The levels of MAPK phosphorylation, 5-HTT mRNA expression and 5-HT uptake all increased in the IFN-alpha-treated cells but were blocked in those that were pretreated with MAPK inhibitors and fluoxetine. These results appear to clarify the association of depression with IFN-alpha-induced 5-HT uptake that reduces the 5-HT levels and IFN-alpha-regulated transcription of 5-HTT; further, the results suggest the involvement of MAPK in this process.

Total recovery of resources and energy from rice straw using microwave-induced pyrolysis.

This article presents the application of microwave-induced pyrolysis to total recovery of resources and energy from rice straw. The microwave power and particle size of feedstock were both key parameters affecting the performance of microwave-induced pyrolysis. Under 400-500W microwave power, the reduction of fixed carbon in the biomass was significant. From the experimental results of specific surface area, zeta potential, and Cu2+ adsorption, the applications of solid residues in the water and wastewater treatment could be expected. The major compositions in gaseous product were H2, CO2, CO, CH4 of 55, 17, 13, 10vol.%, respectively. The high H2 content might imply that microwave-induced pyrolysis of biomass waste has the potential to produce the H2-rich fuel gas. Alkanes, polars, and low-ringed polycyclic aromatic hydrocarbons were three primary kinds of compounds in the liquid product.

Difference in time to x ray with similar time to treatment decision leads to differences in waiting times of patients with hip fracture in a crowded emergency department.

OBJECTIVE: Crowding of patients is common in emergency departments. The number of hip fracture patients not regarded as urgent builds up and patients wait for treatment. In this paper, we present the causes of waiting time and provide some suggestions to improve patient flow in emergency departments. METHODS: We undertook a retrospective review of emergency department records. Included in this study were 112 hip fracture patients seen between January 2005 and January 2007 at an urban, academically affiliated trauma centre. We recorded time to admission, to x ray, and to a definitive treatment decision. Patients were divided into two groups based on time to x ray of < or = 5 min, or > 5 min. RESULTS: There was no difference in the time between taking the x ray and the definitive decision on treatment in the two groups. CONCLUSIONS: We may reduce total waiting time for hip fracture patients by taking an x ray during triage. There are many patients in crowded emergency departments whose symptoms of hip contusion and hip pain, and with a clear history of a fall, are known at admission. Taking an x ray during triage when a patient presents with a typical history and symptoms can reduce total waiting time. We hope that further evaluation could confirm this point.

The removal and recovery of Cr(VI) by Li/Al layered double hydroxide (LDH).

Hexavalent Cr has been identified as one of the toxic metals commonly present in industrial effluents. Among the treatment techniques developed for removing Cr(VI) from waste waters, sorption is most commonly applied, due to its simplicity and efficiency. However, few adsorbents can be recycled and reused cost-effectively. In this study, the removal and recovery of Cr(VI) from water using Li/Al LDH was investigated. The removal of Cr(VI) by Li/Al LDH was evaluated in a batch mode. The results demonstrated that Cr(VI) adsorption onto Li/Al LDH occurs by replacing the Cl(-) that originally exists in the interlayer of the adsorbent. The degree of Cr(VI) adsorption observed for Li/Al LDH was relatively high and the process occurred rapidly; however, a portion of adsorbed Cr(VI) was gradually desorbed, due to the Li de-intercalation of Li/Al LDH. Lithium de-intercalation from Li/Al LDH with interlayer Cl(-) and interlayer Cr(VI) follows the first order kinetics and has the activation energies of 76.6 and 41.5 kJ mol(-1), respectively. The properties of thermal unstability and the high adsorption capacity of Li/Al LDH may lead to the development of an innovative technique for the removal of Cr(VI) from Cr(VI)-containing wastewater. That is, Li/Al LDH may be used as an effective adsorbent for the adsorption of Cr(VI) in an ambient environment. Following the adsorptive process, the adsorbed Cr(VI) may be released, using heated water to treat the Cr(VI)-containing Li/Al LDH particles. Through this hydrothermal treatment of the used adsorbent, Cr(VI) can be recovered and the solid product (gibbsite) can be recycled for further use.

Ceramide in apoptotic signaling and anticancer therapy.

Ceramide, a product of sphingolipid metabolism, is generated in response to various stress stimuli, such as tumor necrosis factor-alpha, CD95/Fas, chemotherapeutic agents, and irradiation. Ceramide may modulate the biochemical and cellular processes that lead to apoptosis. However, the mechanisms by which ceramide regulates apoptotic events are not fully defined. It is believed that the biological effect of ceramide depends on its concentration, the activation or differentiation status of the cell, and the time frame of action. Here, we discuss the metabolism and cell apoptotic signaling of ceramide. The involvement of protein kinases (i.e. PI3K/Akt and GSK-3beta) and protein phosphatases (i.e. PP1 and PP2A), Bcl-2 family proteins, mitochondrial damage, and caspase cascade activation are demonstrated. Further, ceramide and its derivatives have recently been incorporated into strategies for anticancer therapies. An understanding of the apoptotic signaling pathways mediated by ceramide may shed light on its potential for therapeutic intervention.