Evidence that phosphatidylcholine-specific phospholipase C is a key molecule mediating insulin-induced enhancement of gene expression from human cytomegalovirus promoter in CHO cells

The signal transduction from insulin to its receptors and Ras has been extensively studied, while little has been reported beyond these steps. We found that the expression of human interleukin 6 gene under the control of immediate early gene promoter of human cytomegalovirus was enhanced by insulin sitmulation in Chinese hamster ovary cells. The induction effect of insulin was not significantly affected by inhibitors or activators of conventional protein kinase C, cAMP dependent protein kinase and phosphoinositide -3 kinase, however, pre-incubation of the cells with D609, a specific inhibitors of phosphatidylcholine-specific phospholipase C completely abolished the induction effect. These results clearly demonstrate that phosphatidylcholine-specific phospholipase C is a key molecule mediating insulin-induced enhancement of hIL-6 expression from the human cytomegalovirus promoter in Chinese hamster ovary cells and strongly suggest that it plays an important role in the insulin signaling pathways.Abbreviations CHO - Chinese hamster ovary; hCMV promoter - immediate early gene promoter of human cytomegalovirus; hIL-6 - human interleukin 6; PC-PLC-phosphatidylcholine-specific phospholipase C; PI-3 kinase - phosphoinositide 3 kinase; PKA - cAMP dependent protein kinase; PKC - protein kinase C.

Optimization of monoclonal antibody production: combined effects of potassium acetate and perfusion in a stirred tank bioreactor

To increase the yield of monoclonal antibody in a hybridoma culture, it is important to optimize the combination of several factors including cell density, antibody productivity per cell, and the duration of the culture. Potassium acetate enhances the production of antibodies by cells but sometimes depresses cell density. The production of anti-(human B-type red blood cell surface antigen) antibody by Cp9B hybridoma was studied. In batch cultures, potassium acetate inhibited Cp9B cells growth and decreased the maximal cell density but the productivity of antibody per cell was increased. The balance of the two effects resulted in a slight decline of antibody production. In a stirred tank bioreactor, the inhibitory effect of potassium acetate on cell density was overcome by applying the perfusion technique with the attachment of a cell-recycling apparatus to the bioreactor. In such a reactor, potassium acetate at 1 g l(-1) did not cause a decrease in the cell density, and the antibody concentration in the culture supernatant was increased from 28 μg ml(-1) to 38 μg ml(-1). Potassium acetate also suppressed the consumption of glucose and the accumulation of lactate in batch cultures, but the glucose and lactate levels were kept stable by applying the perfusion technique in the stirred tank bioreactor.

The Effects of Exercises on the Relationship between Pulse Transit Time and Arterial Blood Pressure

Pulse transit time (PTT) is one of the physiological parameters that can be utilized to estimate arterial blood pressure (BP) non-invasively. However, the effects of successive exercises on the relationship between PTT and BP have not yet been studied systematically. This study examines the variation in PTT and BP on 15 healthy subjects after treadmill exercise. PTT-peak and PTT-foot, which represent the time intervals from the R-wave of electrocardiogram (ECG) to the peak and the foot of photoplethysmographic (PPG) signal, are verified respectively. ECG, PPG signal, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded from each subject. Experiment was divided into Pre-exercise, Post-exercisel, Post-exercise2, and Recovery. Treadmill exercise was carried out before Post-exersie1 and Post-exercise2. It was found that SBP and DBP increased significantly while PTT-foot and PTT-peak decreased significantly immediately after exercises. During the phase of the Recovery, increment of PTT-foot and hypotension phenomenon was temporarily observed. Throughout the experiments, PTT-foot and BP were inversely related under the effect of two successive exercises. Therefore, it is possible to estimate BP based on the PTT-approach after successive exercises.

Efficient and inducible production of human interleukin 6 in Chinese hamster ovary cells using a novel expression system

High level and inducible production of human interleukin 6 (hIL-6) was achieved using a novel expression system in Chinese hamster ovary (CHO) cells. In this system, the transcription of hIL-6 gene under the control of PhCMV*-1 promoter composed of tetracycline operator sequences and a minimal promoter is activated by a chimeric transactivator (tTA) composed of tetracycline repressor and transactivating domain of VP16 protein of herpes simplex virus. The transcription of tTA gene, which is also under the control of PhCMV*-1 promoter, is activated by itself via a positive feedback cycle. The expression of both genes is further enhanced by potentiating the VP16 transactivating domain of tTA transactivator with pX protein of hepatitis B virus. In the presence of tetracycline, the tTA transactivators can not bind to PhCMV*-1 promoter, therefore, the expression of hIL-6 and tTA gene is suppressed, and the pX will not activate basal transcription. In the absence of tetracycline, tTA transactivators bind to PhCMV*-1 promoter and activate efficient transcription of hIL-6 and tTA gene, and the transcription is further enhanced by pX via VP16 transactivating domain. Using this strategy, we isolated a clone (UX1) producing hIL-6 at a rate about 1425 ng/10(6) cells/day. Furthermore, the hIL-6 production is stringently regulated by tetracycline. This results suggested a novel strategy to establish highly efficient, inducible and cell type independent recombinant protein production system by using an artificial promoter to recruit transactivators and coactivators which can synergistically activate transcription.

The Effects of Epidural Anaesthesia and Analgesia on Natural Killer Cell Cytotoxicity and Cytokine Response in Patients with Epithelial Ovarian Cancer Undergoing Radical Resection

Objective:

Epidural anaesthesia appears to promote antitumourigenic activity in patients with malignant disease who are undergoing surgery. This study investigated immune function in women with epithelial ovarian cancer undergoing radical resection with either general anaesthesia alone or in combination with epidural anaesthesia.

Methods:

Patients ( n = 61) were randomized to receive either combined general/epidural anaesthesia (study group) or general anaesthesia alone (control group). Natural killer cell cytotoxicity (NKCC) and serum concentrations of four cytokines (interleukin [IL]-1β, -8 and -10 and interferon [IFN]-γ) were measured before anaesthesia ( Tpre) and 4h after skinincision ( T4 h) in both groups.

Results:

In both groups, concentrations of protumourigenic cytokines (IL-1β and IL-8) were significantly higher at T4 h than at Tpre, while concentrations of antitumourigenic cytokines (IL-10 and IFN-γ) and NKCC were significantly lower at T4 h. The study group had significantly higher NKCC, IL-10 and IFN-γ levels and lower IL-1β and IL-8 levels at TT h compared with the control group.

Conclusion:

Combined general/epidural anaesthesia appeared to promote antitumourigenic NKCC and cytokine responses.

Increased platelet activation and thrombosis in transgenic mice expressing constitutively active P2Y12

BACKGROUND

In our previous in vitro study, we reported a constitutively active chimeric P2Y(12) (cP2Y(12)) and found that AR-C78511 is a potent inverse agonist at this receptor. The role of cP2Y(12) in platelet activation and thrombosis is not clear.

OBJECTIVES

To investigate the physiologic implications of cP2Y(12) for platelet activation and thrombus formation, and to evaluate the antiplatelet activity of AR-C78511 as an inverse agonist.

METHODS AND RESULTS

We generated transgenic mice conditionally and platelet-specifically expressing cP2Y(12). High-level expression of cP2Y(12) in platelets increased platelet reactivity, as shown by increased platelet aggregation in response to multiple platelet agonists. Moreover, transgenic mice showed a shortened bleeding time, and more rapid and stable thrombus formation in mesenteric artery injured with FeCl(3). The constitutive activity of cP2Y(12) in platelets was confirmed by decreased platelet cAMP levels and constitutive Akt phosphorylation in the absence of agonists. AR-C78511 reversed the cAMP decrease in transgenic mouse platelets, and exhibited a superior antiplatelet effect to that of AR-C69931MX in transgenic mice.

CONCLUSIONS

These findings further emphasize the importance of P2Y(12) in platelet activation, hemostasis, and thrombosis, as well as the prothrombotic role of the constitutive activity of P2Y(12). Our data also validate the in vivo inverse agonist activity of AR-C78511, and confirm its superior antiplatelet activity over neutral antagonists.

Pasireotide (SOM230) shows efficacy and tolerability in the treatment of patients with advanced neuroendocrine tumors refractory or resistant to octreotide LAR: results from a phase II study

Pasireotide (SOM230) is a novel multireceptor-targeted somatostatin (sst) analog with high binding affinity for sst receptor subtype 1, 2, 3 (sst(1,2,3)) and sst(5). Because of this binding profile, pasireotide may offer symptom control in patients with neuroendocrine tumors (NETs) and carcinoid syndrome no longer responsive to octreotide LAR. This was a phase II, open-label, multicenter study of pasireotide in patients with advanced NET whose symptoms of carcinoid syndrome (diarrhea/flushing) were inadequately controlled by octreotide LAR. Patients received s.c. pasireotide 150 μg twice daily (bid), escalated to a maximum dose of 1200 μg bid until a clinical response was achieved. Forty-four patients were evaluated for efficacy and 45 for tolerability. Pasireotide 600-900 μg s.c. bid effectively controlled the symptoms of diarrhea and flushing in 27% of patients. Evaluation of tumor response in 23 patients showed 13 with stable disease and ten with progressive disease at study end. The most common drug-related adverse events were nausea (27%), abdominal pain (20%), weight loss (20%), and hyperglycemia (16%) and most were of mild or moderate severity. Pasireotide 600-900 μg s.c. bid was effective and generally well tolerated in controlling the symptoms of carcinoid syndrome in 27% of patients with advanced NET refractory or resistant to octreotide LAR therapy.

Association between C-reactive Protein Concentration and Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-analysis

Objective:

This meta-analysis was conducted to summarize the association between the serum concentration of C-reactive protein (CRP) and chronic obstructive pulmonary disease (COPD).

Methods:

MEDLINE®, Cochrane Central Register of Controlled Trials, and EMBASE databases were searched for relevant studies. Data were extracted; pooled weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated.

Results:

Twenty studies were selected for final inclusion in this analysis. Patients with COPD had higher serum CRP concentrations than healthy controls (WMD 4.72 mg/l, 95% CI 2.98, 6.47). In addition, patients with severe COPD had higher serum CRP concentrations than those with moderate COPD (WMD 1.26 mg/l, 95% CI 0.78, 1.73). There was no significant difference in serum CRP concentration between patients with mild and moderate COPD (WMD 0.67 mg/l, 95% CI -0.08, 1.42).

Conclusions:

This meta-analysis suggested that patients with stable COPD had higher serum CRP concentrations than healthy controls. CRP might be an indicator of disease severity in patients with COPD, thus highlighting the importance of measuring serum CRP concentrations in patients with stable COPD.

Risk Factors for Developing Pneumonia in Patients with Diabetes Mellitus Following Acute Ischaemic Stroke

Objectives:

To evaluate markers of infection and identify risk factors for the development of pneumonia following acute ischaemic stroke in patients with diabetes mellitus.

Methods:

Patients with diabetes mellitus ( n = 106) who were hospitalized after acute ischaemic stroke with ( n = 32) or without ( n = 74) pneumonia at admission were included in the study. Levels of C-reactive protein (CRP) and interleukin-6 (IL-6), white blood cell (WBC) count, mean body temperature and severity of stroke on the National Institutes of Health Stroke Scale were measured at the time of admission. The degree of disability according to the modified Rankin Scale was assessed after 30 days.

Results:

Raised levels of IL-6 and CRP, older age, more severe stroke, longer duration of hospitalization and dysphagia were significantly associated with the development of pneumonia. Patients with pneumonia had significantly worse outcomes compared with nonpneumonia patients after 1 month. Raised WBC count and mean body temperature were not significant predictors of pneumonia.

Conclusions:

Markers of infection, more severe ischaemic stroke, dysphagia and older age may help in predicting the occurrence of pneumonia at stroke onset.

Efficacy and Safety of an Intra-operative Intra-articular Magnesium/Ropivacaine Injection for Pain Control following Total Knee Arthroplasty

Eighty patients with osteoarthritis who underwent unilateral total knee arthroplasty were randomly assigned to two groups: the trial group received an intraoperative intra-articular injection of magnesium sulphate and ropivacaine, and the control group received an injection of normal saline. All patients received patient-controlled analgesia with morphine for 48 h post-operatively. It was found that an intra-articular injection of magnesium sulphate and ropivacaine significantly reduced morphine consumption during the 0 - 24 h post-operative period and total 48-h postoperative morphine consumption. Pain scores at rest and during motion in the trial group were significantly lower than in the controls during the first 24 h post-operatively. The time to be able to perform a straight leg raise and to reach a 90° knee flexion was significantly shorter in the trial group compared with the controls. This study demonstrated that an intra-operative intra-articular magnesium sulphate and ropivacaine injection reduced the use of post-operative morphine.

Highly stable and regenerable Mn-based/SBA-15 sorbents for desulfurization of hot coal gas

A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700-850°C. The successive nine desulfurization-regeneration cycles at 800°C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn(2)O(3) particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800°C is 13.8 g S/100g sorbents, which is remarkably higher than these of 40 wt%LaFeO(3)/SBA-15 (4.8 g S/100g sorbents) and 50 wt%LaFe(2)O(x)/MCM-41 (5.58 g S/100g sorbents) used only at 500-550°C. This suggested that the loading of Mn(2)O(3) active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization.

Observation of B0→D¯(0)K(+)K(-) and evidence for B(s)(0)→D¯(0)K(+)K(-)

The first observation of the decay B0→D¯(0)K(+)K(-) is reported from an analysis of 0.62 fb(-1) of pp collision data collected with the LHCb detector. Its branching fraction is measured relative to that of the topologically similar decay B(0)→D ¯(0)π(+)π(-) to be (B(B(0)→D¯(0)K(+)K(-))/B(B(0)→D¯(0)π(+)π(-))=0.056±0.011±0.007,where the first uncertainty is statistical and the second is systematic. The significance of the signal is 5.8σ. Evidence, with 3.8σ significance, for B(s)(0)→D¯(0)K(+)K(-) decays is also presented. The relative branching fraction is measured to be B(B(s)(0)→D¯(0)K(+)K(-))/B(B(0)→D¯(0)K(+)K(-))=0.90±0.27±0.20. These channels are of interest to study the mechanisms behind hadronic B decays, and open new possibilities for CP violation analyses with larger data sets.

Biomarkers in the lung cancer diagnosis: a clinical perspective

The propensity for tumor biomarkers to be detected in serum at an early disease stage has become an area of interest for clinicians. This study aimed to evaluate the efficiency of 7 tumor biomarkers, namely, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), cytokeratin 19 (CYFRA-21-1), alpha-fetoprotein, carbohydrate antigen-125 (CA-125), carbohydrate antigen-19.9 (CA-19.9), and ferritin, independently or in combination for the diagnosis of lung cancer. Electrochemiluminescence immunization was used to determine biomarker levels expressed in 530 patients with pulmonary disease and 229 healthy subjects. The observed levels of CEA, NSE, CYFRA-21-1, CA-125, and CA-19.9 in patients with pathologically confirmed lung cancer were significantly higher than those in patients with benign pulmonary disease or control subjects. Adenocarcinoma, squamous cell carcinoma, and small cell carcinoma of the lung were associated with the highest observed levels of CA-125, CYFRA-21-1, and NSE, respectively. Combining biomarkers successfully led to the diagnosis of lung cancer. CEA + NSE + CA-125 showed the highest sensitivity for small cell carcinoma, at 83.33%, whereas CEA + NSE + CYFRA-21-1 + CA-125 showed 94.11% sensitivity for squamous cell carcinoma. The combination of 6 biomarkers, namely, CEA + NSE + CYFRA-21-1 + CA-125 + ferritin + CA-19.9, showed 80.49% sensitivity for adenocarcinoma. Combining biomarkers significantly aided in the diagnosis of lung cancer. However, this increased sensitivity on combination was accompanied by a decreased specificity for lung cancer subtypes. Combining biomarkers appropriately increases their sensitivity and helps with the diagnosis of lung cancer.

Evaluation of the GenoType® MTBDRplus assay and identification of a rare mutation for improving MDR-TB detection

OBJECTIVE

To assess the new GenoType® MTBDRplus assay for the rapid detection of multidrug-resistant tuberculosis (MDR-TB) in comparison with DNA sequencing to identify drug resistance mutation profiles in China.

DESIGN

Using MTBDRplus, drug susceptibility testing (DST) and DNA sequencing, 237 Mycobacterium tuberculosis strains were tested.

RESULTS

The sensitivity of MTBDRplus was 75.0% (126/168) for isoniazid (INH) resistant strains, and 93.5% (157/168) for rifampicin (RMP) resistant strains. It correlated well with sequencing, with 94.9% and 99.6% agreement for each strain category and 100% specificity for all categories. The two most common rpoB mutations were S531L (53.6%, 90/168) and D516G (17.3%, 29/168) in RMP-resistant strains. INH resistance was dominated by the katG 315 locus (S to T, N, R, I) mutation (73.7%, 124/168), and a rare katG mutation, S315N (6.5%, 11/168), not covered by MTBDRplus was identified. The mutation combination inhA-15/inhA-8 and katG315 (34 strains) was characteristically displayed in MDR-TB strains (23.5%), but not in INH-monoresistant strains.

CONCLUSIONS

Although Genotype MTBDRplus is a rapid and reliable molecular test for detecting MDR-TB, a significant proportion of strains in China contain a rare katG S315N mutation that would be missed by the assay. Further improvements may be achieved by incorporating this mutation into the assay to increase sensitivity in detecting INH resistance in China.

Polymorphisms in the SLC11A1 gene and tuberculosis risk: a meta-analysis update

BACKGROUND

Polymorphisms in SLC11A1 gene have been extensively studied for an association with tuberculosis (TB); however, results from replication studies have been inconsistent.

OBJECTIVE

To comprehensively evaluate the genetic risk of polymorphisms (D543N, 3'UTR TGTG ins/del, INT4, [GT]n) in the SLC11A1 gene for TB.

METHODS

A meta-analysis was carried out to analyse the association between SLC11A1 polymorphisms and TB risk.

RESULTS

A total of 82 case-control studies in 35 articles were included in the meta-analysis. The results showed that these four polymorphisms were associated with an increased risk of TB (D543N OR 1.31, 95%CI 1.11-1.55; 3'UTR TGTG ins/del OR 1.45, 95%CI 1.25-1.68; INT4 OR 1.27, 95%CI 1.09-1.49; [GT]n OR 1.35, 95%CI 1.14-1.61). In further stratified analyses by ethnicity and TB forms, significant increased risks were found in subgroups of Asians and in pulmonary TB (PTB) for all four polymorphisms, while an increased risk of extra-pulmonary TB (EPTB) was found for D543N polymorphism.

CONCLUSIONS

This meta-analysis suggests that polymorphisms in the SLC11A1 gene contribute to TB (both PTB and EPTB), particularly in Asians.

Cyclosporine induces up-regulation of immunoglobulin-like transcripts 3 and 4 expression on and activity of NKL cells

BACKGROUND

Immunoglobulin-like transcripts (ILTs), which belong to a kind of receptor family discovered recently, are differentially expressed on myeloid and lymphoid cells. Most of them play important roles to regulate human immune responses by interacting with ligands. Cyclosporine (CsA) is frequently used to prevent graft-versus-host disease and treat autoimmune diseases. There are some studies about the effects of CsA on various human immunologic reactions, but its impact on ILT3 and ILT4 expression on natural killer (NK) cells is less well understood.

METHODS

An NKL cell line was exposed to CsA (5, 10, 15, or 20 mg/L) for 12, 24, or 36 hours before real-time quantitative polymerase chain reaction and flow cytometry were used to detect alterations in ILT3 and ILT4 mRNA and protein expressions. NKL cells treated for 36 hours with or without CsA (15 mg/L) and then coincubated with BGC-823 or JEG-3 cells, in cytolytic and proliferative systems measured by Thiazoyl blue tetrazolium bromide assays.

RESULTS

After CsA treatment both RNA and protein levels of ILT3 and ILT4 on NKL cells were increased for 12, 24, or 36 hours. CsA at various concentrations inhibited the proliferation of NKL cells to varying degrees; at 36 hours CsA (15 mg/L) showed greater effects on ILT3 and ILT4 expression and less influence on NKL growth. The ability of NKL cells primed with CsA (15 mg/L) for 36 hours to kill tumor cells was decreased markedly.

CONCLUSIONS

CsA up-regulated the expression of ILT3 and ILT4 on NKL cells, which influenced their cytotoxicity against tumor cells with different expression of HLA-G and proliferation of NKL cells.

Nitrogen and phosphorus use efficiencies and losses in the food chain in China at regional scales in 1980 and 2005

Crop and animal production in China has increased significantly during the last decades, but at the cost of large increases in nitrogen (N) and phosphorus (P) losses, which contribute to ecosystem degradation and human health effects. This information is largely based on scattered field experiments, surveys and national statistics. As a consequence, there is as yet no comprehensive understanding of the changes in N and P cycling and losses at regional and national scales. Here, we present the results of an integrated assessment of the N and P use efficiencies (NUE and PUE) and N and P losses in the chain of crop and animal production, food processing and retail, and food consumption at regional scale in 1980 and 2005, using a uniform approach and databases. Our results show that the N and P costs of food production-consumption almost doubled between 1980 and 2005, but with large regional variation. The NUE and PUE of crop production decreased dramatically, while NUE and PUE in animal production increased. Interestingly, NUE and PUE of the food processing sector decreased from about 75% to 50%. Intake of N and P per capita increased, but again with large regional variation. Losses of N and P from agriculture to atmosphere and water bodies increased in most regions, especially in the east and south of the country. Highest losses were estimated for the Beijing and Tianjin metropolitan regions (North China), Pearl River Delta (South China) and Yangzi River Delta (East China). In conclusion, the changes and regional variations in NUE and PUE in the food chain of China are large and complex. Changes occurred in the whole crop and animal production, food processing and consumption chain, and were largest in the most populous areas between 1980 and 2005.