Effect of short term calorie restriction on pro-inflammatory NF-kB and AP-1 in aged rat kidney

OBJECTIVE

To compare the effect of short-term calorie restriction (CR) on aging with that of already known long-term CR, the anti-inflammatory efficacy of 10-day CR was explored in aged rat kidney.

TREATMENT

Two different age groups, 6 months (young) and 24 months (old) were used. In the old group, one sub-group was control, fed ad libitum (AL) and the other was fed CR for 10 days with 40 % of the food intake of the AL subgroup (n = 5).

METHODS

Reactive species (RS), lipid peroxides and COX-2 activity were measured. The activities of proinflammatory transcription factors NF-kB and AP-1 were measured by electro-mobility shift assay (EMSA). Upstream signaling cascades of NF-kB and AP-1 as well as proinflammatory gene expression were detected by Western blot.

RESULTS

10-day CR suppressed RS, lipid peroxides, and COX-2 activity in aged rat kidney. CR also inhibited upstream signaling cascades and DNA binding activity of NF-kB and AP-1, and thioredoxin/Ref-1 pathway. CR blocked expression of NF-kB-and AP-1-responsive gene COX-2, iNOS, VCAM-1 and ICAM-1.

CONCLUSIONS

We report for the first time that 10-day CR can attenuate the altered signaling transduction for inflammatory processes which is mediated through RS-induced NF-kB and AP-1 in aged kidney.

MRP- and BCL-2-mediated drug resistance in human SCLC: effects of apoptotic sphingolipids in vitro

Multidrug-resistance-associated protein (MRP) and BCL-2 contribute to drug resistance expressed in SCLC. To establish whether MRP-mediated drug resistance affects sphingolipid (SL)-induced apoptosis in SCLC, we first examined the human SCLC cell line, UMCC-1, and its MRP over-expressing, drug-resistant subline, UMCC-1/VP. Despite significantly decreased sensitivity to doxorubicin (Dox) and to the etoposide, VP-16, the drug-selected line was essentially equally as sensitive to treatment with exogenous ceramide (Cer), sphingosine (Sp) or dimethyl-sphingosine (DMSP) as the parental line. Next, we observed that high BCL-2-expressing human H69 SCLC cells, that were approximately 160-fold more sensitive to Dox than their combined BCL-2 and MRP-over-expressing (H69AR) counterparts, were only approximately 5-fold more resistant to DMSP. Time-lapse fluorescence microscopy of either UMCC cell line treated with DMSP-Coumarin revealed comparable extents and kinetics of SL uptake, further ruling out MRP-mediated effects on drug uptake. DMSP potentiated the cytotoxic activity of VP-16 and Taxol, but not Dox, in drug-resistant UMCC-1/VP cells. However, this sensitization did not appear to involve DMSP-mediated effects on the function of MRP in drug export; nor did DMSP strongly shift the balance of pro-apoptotic Sps and anti-apoptotic Sp-1-Ps in these cells. We conclude that SL-induced apoptosis markedly overcomes or bypasses MRP-mediated drug resistance relevant to SCLC and may suggest a novel therapeutic approach to chemotherapy for these tumors.

High precision high voltage divider and its application to electron beam ion traps

A high precision high voltage divider has been developed for the electron beam ion trap in Shanghai. The uncertainty caused by the temperature coefficient of resistance (TCR) and the voltage coefficient of resistance has been studied in detail and was minimized to the level of ppm (10(-6)) range. Once the TCR was matched between the resistors, the precision of the dividing ratio finally reached the ppm range also. We measured the delay of the divider caused by the capacitor introduced to minimize voltage ripple to be 2.35 ms. Finally we applied the divider to an experiment to measure resonant energies for some dielectronic recombination processes for highly charged xenon ions. The final energies include corrections for both space charge and fringe field effects are mostly under 0.03%.

High resolution flat crystal spectrometer for the Shanghai EBIT

We report on a high resolution flat crystal spectrometer designed for the Shanghai EBIT. Its energy range is from 0.5 to 10 keV. Three crystals can be installed in the vacuum chamber simultaneously, and its effective Bragg angle can be covered from 15 degrees to 75 degrees . A vacuum version charge-coupled device detector is used for detection of photons. An energy resolution under 1 eV was reached in measurements of the 4.5 keV Kalpha(1) line by using an x-ray generator with a titanium anode. The spectrometer was also tested to operate well on the Shanghai EBIT by observing the lines of tungsten at around 3.2 keV.

Exon skipping mutations in collagen VI are common and are predictive for severity and inheritance

Mutations in the genes encoding collagen VI (COL6A1, COL6A2, and COL6A3) cause Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD), two related conditions of differing severity. BM is a relatively mild dominantly inherited disorder characterized by proximal weakness and distal joint contractures. UCMD was originally regarded as an exclusively autosomal recessive condition causing severe muscle weakness with proximal joint contractures and distal hyperlaxity. We and others have subsequently modified this model when we described UCMD patients with heterozygous in-frame deletions acting in a dominant-negative way. Here we report 10 unrelated patients with a UCMD clinical phenotype and de novo dominant negative heterozygous splice mutations in COL6A1, COL6A2, and COL6A3 and contrast our findings with four UCMD patients with recessively acting splice mutations and two BM patients with heterozygous splice mutations. We find that the location of the skipped exon relative to the molecular structure of the collagen chain strongly correlates with the clinical phenotype. Analysis by immunohistochemical staining of muscle biopsies and dermal fibroblast cultures, as well as immunoprecipitation to study protein biosynthesis and assembly, suggests different mechanisms each for exon skipping mutations underlying dominant UCMD, dominant BM, and recessive UCMD. We provide further evidence that de novo dominant mutations in severe UCMD occur relatively frequently in all three collagen VI chains and offer biochemical insight into genotype-phenotype correlations within the collagen VI-related disorders by showing that severity of the phenotype depends on the ability of mutant chains to be incorporated in the multimeric structure of collagen VI.

Administration of intracoronary bone marrow mononuclear cells on chronic myocardial infarction improves diastolic function

BACKGROUND

Regeneration of the myocardium and improved ventricular function have been demonstrated in patients with acute myocardial infarction (MI) treated by intracoronary delivery of autologous bone marrow mononuclear cells (BMC) a few days after successful myocardial reperfusion by percutaneous coronary intervention (PCI); however, the effects of intracoronary cell infusion in chronic MI patients are still unknown.

AIMS

To investigate whether intracoronary infusion of BMC into the infarct-related artery in patients with healed MI could lead to improvement in left ventricular (LV) function.

METHODS

Among 47 patients with stable ischaemic heart disease due to a previous MI (13 (SD 8) months previously), 24 were randomised to intracoronary infusion of BMC (BMC group) and 23 to a saline infusion (control group) into the target vessel after successful PCI within 12 hours after chest pain occurred. LV systolic and diastolic function, infarct size and myocardial perfusion defect were assessed with the use of echocardiography, magnetic resonance imaging (MRI) or (201)Tl single-photon-emission computed tomography (SPECT) at baseline and repeated at the 6-month follow-up examination.

RESULTS

BMC treatment did not result in a significant increase in LV ejection fraction in any of the groups by any of the methods used, and the apparent tendency of an improvement was not statistically different between the two groups. The two groups also did not differ significantly in changes of LV end-diastolic and systolic volume, infarct size or myocardial perfusion. However, there was an overall effect of BMC transfer compared with the control group with respect to early/late (E/A) (p<0.001), early diastolic velocity/late diastolic (Aa) velocity (Ea/Aa) ratio (p = 0.002) and isovolumetric relaxation time (p = 0.038) after 6 months, as evaluated by tissue Doppler echocardiography. We noted no complications associated with BMS transfer.

CONCLUSION

Intracoronary transfer of autologous BMC in patients with healed MI did not lead to significant improvement of cardiac systolic function, infarct size or myocardial perfusion, but did lead to improvement in diastolic function.

Cryoablation induces necrosis and apoptosis in lung adenocarcinoma in mice

This study evaluated cryoablation on subcutaneously transplanted tumors of lung adenocarcinoma LA795 in T739 mice in vivo, in an effort to assess the feasibility of cryoablation in treatment of NSCLC. Subcutaneously transplanted lung adenocarcinoma LA795 was implanted into T739 mice yielding tumors of approximately 2.5 cm in diameter. Following cryoablation, the various modes of cell death were studied: necrosis in the central frozen zone by light microscopy and apoptosis in periphery of the frozen zone by in situ end labeling (TUNEL). Bc1-2 and bax expression were detected by immunohistochemical SABC procedures, and the cleavage and activation of Caspase 3 and PARP in peripheral zone by Western blot. We find that in central cryoablated zone, necrosis was the dominant mode of cell death occurring at three hours and four days post-thaw. The first three-hour necrosis peak involved approximately 47% of the tumor while the four-day peak increased in volume to 68% of the tumor. In peripheral cryoablation zone, definite cell apoptosis could be observed by morphological examination under light microscope and TUNEL staining, peaking at 8-16 h after cryoablation. Immunohistochemical results yielded little change in bcl-2 protein expression before and after cryoablation. However, bax protein expression was up-regulated significantly after cryoablation. In addition, cleavage and activation of Caspase-3 and PARP occurred in the peripheral freeze zone after the treatment. It indicated that Cryoablation efficiently induces cell death both by necrosis and apoptosis. Cryoablation appears to induce apoptosis in the peripheral freeze zone through the intrinsic mitochondrial caspase pathway based on bax upregulation. This observation allows us to suggest that cryoablation may be combined with chemotherapy to increase cancer destruction.

Distinguishing quasiperiodic dynamics from chaos in short-time series

We propose a procedure to distinguish quasiperiodic from chaotic orbits in short-time series, which is based on the recurrence properties in phase space. The histogram of the return times in a recurrence plot is introduced to disclose the recurrence property consisting of only three peaks imposed by Slater's theorem. Noise effects on the statistics are studied. Our approach is demonstrated to be efficient in recognizing regular and chaotic trajectories of a Hamiltonian system with mixed phase space.

Steroids and immunosuppressive agents potentiate the cytotoxicity of the EGFR inhibitor erlotinib (E) in human skin keratinocytes whereas Vit K3 exerts a protective effect: Implications for the management of the skin rash

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Background: Skin toxicity secondary to EGFR inhibitors is treated symptomatically with topical and systemic combinations of steroids, antibiotics, antihistamines, and immunosuppressive agents with variable and often unsatisfactory results. Vit K3 prevents EGFR inhibition induced by E and cetuximab in human A431 tumor cells, probably through an effect on the phosphatase (Perez-Soler, ASCO 2006). We studied the cytotoxic effects of different agents used to treat the EGFR inhibitor-mediated skin rash on human immortalized skin keratinocytes exposed to the EGFR inhibitor E as well as the potential protective effect of Vit K3. Methods: The cytotoxicity of E in the presence of non cytotoxic concentrations of hydrocortisone, minocycline, cyclosporine-A, diphenhydramine, and Vit K3 was assessed by MTT assay in human HaCat cells, a cell line derived from human basal epidermal cells. Results: E cytotoxicity was enhanced by 2–5 fold by cyclosporine A and hydrocortisone, not affected by minocycline and diphenhydramine, and reduced by 5-fold by Vit K3. Vit K3 25–50 μM induced EGFR activation and prevented E's inhibitory effect on EGFR. Conclusions: Steroids and immunosuppressive agents may potentiate the cytotoxic effect of anti-EGFR agents in the skin, thus providing a possible explanation for the erratic and mixed therapeutic results often observed with the use of these agents. Vit K3 was the only agent capable of abrogating the cytotoxic effect of E in this clinically relevant model of normal human skin. A topical formulation of Vit K3 is undergoing preclinical evaluation. Supported by NCI CA 91784 and 113630 and a grant from Hana Biosciences.

No significant financial relationships to disclose.

Deep vein thrombosis in trauma: a prospective study of lower limb orthopedic trauma patients in Tianjin Hospital, China

AIM

Pulmonary embolism is a third leading cause of death in trauma patients. The prevalence of deep vein thrombosis (DVT) in Asian countries is considered to be less than in Western countries. Our aim was to establish the rate of DVT in orthopedic trauma patients in Tianjin Hospital, to identify DVT risk factors and to support the use of prophylaxis.

METHODS

Patients admitted between November 2003 and October 2004 with recent fracture had data collected prospectively to record type of fracture, mechanism of injury, history of DVT, blood transfusion requirements, operation details, extent of postoperative swelling, use of traction, immobilization, bandaging and patient positioning. Each patient had 3 duplex ultrasound examinations, the first within 24 h of admission. Patients requiring surgery had a second ultrasound within 2 days preoperatively, then 7 days postoperatively. Patients not requiring surgery had second and third ultrasound examinations 5 and 14 days after admission.

RESULTS

There were 547 patients, median age 39.6 years (interquartile range: 28-50 years). DVT developed in 12.4% (95% confidence interval: 9.7-15.2%), most occurring with femoral shaft fractures (30.6%), 15.8% occurred with hip fractures, 14.5% with fractures around the knee and 10.8% with fractured tibia and fibula. Over half of DVTs (56.7%) developed within 3 days following injury.

CONCLUSION

The incidence of DVT in Chinese orthopedic trauma patients approaches that in Western countries. Guidelines for DVT prophylaxis should be applied in China as in Western countries.