[Adenovirus mediated N19RhoA gene transfer attenuates neointimal formation in rats after carotid artery balloon injury]

OBJECTIVE

To investigate the role of small G-protein RhoA in neointimal formation following rat carotid artery balloon injury and related mechanisms.

METHODS

Male 3-4-month-old Sprague-Dawley rats were used in the present study (10 rats per group). Group A: control; Group B: carotid artery balloon injury; Group C: injury + Ad-CMV-eGFP + Pluronic F-127; Group D: injury + Ad-CMV-N19RhoA-eGFP + Pluronic F-127; Group E: non injury + Ad-CMV-eGFP + Pluronic F-127. Perivascular gene transfer of an adenovirus co-expressing N19RhoA was performed to rat carotid artery following balloon injury and the effect on neointimal formation and the expressions of PCNA and α-SM-actin examined. Rats were killed after 14 days.

RESULTS

The protein expression of RhoA in group B was significantly higher than in group A (P = 0.001), and the positive cells rate of PCNA and α-SM-actin which were assessed by immunohistochemistry in group C (45.2% and 75.6%) was significantly higher than in group D (28.4% and 51.9%, all P < 0.01). The area of neointima was significantly smaller [(0.14 ± 0.08) mm(2) vs. (0.23 ± 0.10) mm(2), P < 0.01], the luminal area was significantly larger [(0.47 ± 0.11) mm(2) vs. (0.31 ± 0.06) mm(2), P < 0.01] in group D than in group C.

CONCLUSION

Gene transfer of N19RhoA attenuates neointimal formation after balloon injury in rat carotid arteries possibly related to the modulating capacities of small G-protein RhoA on the proliferation, phenotypic differentiation and migration of vascular adventitial fibroblasts.

[The effects of joint administration of 6% hydroxyethyl starch 130/0.4 and high-volume hemofiltration on patients with acute lung injury and acute kidney injury]

OBJECTIVE

To evaluate the effects of administration of 6% hydroxyethyl starch (6% HES 130/0.4, voluven) in combination with high volume hemofiltration (HVHF) in patients with ALI and AKI.

METHODS

One hundred and eight patients with acute lung injury (ALI) and acute kidney injury (AKI) were enrolled from Department of Intensive Care Unit (ICU) of the provincial Hospital Affiliated to Shandong University between August 2006 and May 2011. The patients were randomly divided into two groups A (n = 68) and B (n = 40) to receive voluven (i.v., for volume resuscitation) and voluven+HVHF for 72 hours. The arterial blood lactate concentration (Lac), high sensitivity C-reactive protein (hs-CRP) serum concentration, pulmonary function index alveolar-arterial oxygen pressure difference [P(A-a)DO2] and oxygenation index (OI), as well as kidney function index serum cystatin C (Cyst C) and serum creatinine clearance rate (CCr) were measured at the time of admission and 72 hours after the treatment for statistical analysis.

RESULTS

In comparison with group A, group B had significantly (all P < 0.01) lower mean value in the level of arterial Lac (mmol/L: 1.7 ± 0.7 vs. 2.7 ± 1.5), serum hs-CRP (mg/L: 35.8 ± 18.8 vs. 99.5 ± 20.4), P(A-a)DO2 (mm Hg, 1 mm Hg=0.133 kPa: 115.5 ± 23.1 vs. 155.4 ± 27.4), Cyst C (mg/L: 2.06 ± 1.12 vs. 3.95 ± 2.06) and significantly higher (both P < 0.01) mean value of OI (mm Hg: 295.2 ± 38.8 vs. 239.5 ± 32.7) and CCr (ml/min: 108.71 ± 31.33 vs. 90.21 ± 30.35) 72 hours after treatment. The mortality rate of group B was significantly lower than group A [10.00%(4/40) vs. 29.41%(20/68), P < 0.05] 7 days after the admission.

CONCLUSION

6% HES 130/0.4 in combination with HVHF could improve the lung and kidney function of the patients with ALI and AKI, prevent the development of multiple organ dysfunction syndrome (MODS), therefore improve the survival rate of these patients.

A solid phase extraction-liquid chromatographic-tandem mass spectrometry method for determination of concentrations of GDC-0941, a small molecule class I phosphatidylinositide 3-kinase inhibitor, to support clinical development

A solid phase extraction (SPE) liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for the determination of GDC-0941 concentrations in human plasma has been developed and validated to support clinical development. An Oasis MCX 10mg 96-well SPE plate was used to extract plasma samples (50 μL) and the resulting extracts were analyzed using reverse-phase chromatography and mass spectrometer coupled with a turbo-ionspray interface. The method was validated over the calibration curve range 0.500-500 ng/mL with linear regression and 1/x(2) weighting. Within-run relative standard deviation (%RSD) ranged from 1.5 to 11.5%, while the between-run %RSD varied from 0.0 to 4.4%. The accuracy ranged from 96.0% to 110.0% of nominal for within-run and 98.0% to 108.0% of nominal for between-run at all concentrations including the LLOQ quality control at 0.500 ng/mL. Extraction recovery of GDC-0941 was between 79.0% and 86.2%. Stability of GDC-0941 was established in human plasma for 602 days at -70 °C and 598 days at -20°C, respectively, and established in reconstituted sample extracts for 167 h when stored at room temperature. Internal standard normalized matrix factor was 1.1, demonstrating that the use of the stable-labeled internal standard GDC-0941-d(8) effectively compensated observed matrix effect and resulting in no adverse impact on the quality of the data produced. This assay was used for the determination of GDC-0941 human plasma concentrations over a sufficient time period to determine pharmacokinetic parameters at relevant clinical doses.

Effects of high-volume hemofiltration on alveolar-arterial oxygen exchange in patients with refractory septic shock

BACKGROUND

High-volume hemofiltration (HVHF) is technically possible in severe acute pancreatitis (SAP) patients complicated with multiple organ dysfunction syndrome (MODS). Continuous HVHF is expected to become a beneficial adjunct therapy for SAP complicated with MODS. In this study, we aimed to explore the effects of fluid resuscitation and HVHF on alveolar-arterial oxygen exchange, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score in patients with refractory septic shock.

METHODS

A total of 89 refractory septic shock patients, who were admitted to ICU, the Provincial Hospital affiliated to Shandong University from August 2006 to December 2009, were enrolled in this retrospective study. The patients were randomly divided into two groups: fluid resuscitation (group A, n=41), and fluid resuscitation plus high-volume hemofiltration (group B, n=48). The levels of O2 content of central venous blood (CcvO2), arterial oxygen content (CaO2), alveolar-arterial oxygen pressure difference P(A-a)DO2, ratio of arterial oxygen pressure/alveolar oxygen pressure (PaO2/PaO2), respiratory index (RI) and oxygenation index (OI) were determined. The oxygen exchange levels of the two groups were examined based on the arterial blood gas analysis at different times (0, 24, 72 hours and 7 days of treatment) in the two groups. The APACHE II score was calculated before and after 7-day treatment in the two groups.

RESULTS

The levels of CcvO2, CaO2 on day 7 in group A were significantly lower than those in group B (CcvO2: 0.60±0.24 vs. 0.72±0.28, P<0.05; CaO2: 0.84±0.43 vs. 0.94±0.46, P<0.05). The level of oxygen extraction rate (O2ER) in group A on the 7th day was significantly higher than that in group B (28.7±2.4 vs. 21.7±3.4, P<0.01). The levels of P(A-a)DO2 and RI in group B on the 7th day were significantly lower than those in group A. The levels of PaO2/PaO2 and OI in group B on 7th day were significantly higher than those in group A (P<0.05 or P<0.01). The APACHE II score in the two groups reduced gradually after 7-day treatment, and the APACHE II score on the 7th day in group B was significantly lower than that in group A (8.2±3.8 vs. 17.2±6.8, P<0.01).

CONCLUSION

HVHF combined with fluid resuscitation can improve alveolar-arterial-oxygen exchange, decrease the APACHE II score in patients with refractory septic shock, and thus it increases the survival rate of patients.

[The role of p38 mitogen-activated protein kinase in interleukin-6 induction by lipopolysaccharide in vascular smooth muscle cells]

OBJECTIVE

To investigate the regulation mechanism of p38 mitogen-activated protein kinase (p38MAPK) in interleukin-6 (IL-6) expression of vascular smooth muscle cell (VSMC) induced by lipopolysaccharide (LPS).

METHODS

Rat VSMCs were divided into LPS group, SB203580+LPS group, SB203580 group and control group. LPS group was treated with 100 microg/L LPS for 0, 3, 6, 12, 24 hours, SB203580+LPS group was first treated with 10 micromol/L SB203580 for 2 hours and then exposed to 100 microg/L LPS for 0, 3, 6, 12, 24 hours, SB203580 group was pretreated with 10 micromol/L SB203580 for 2 hours. The level of IL-6 mRNA was determined by real-time polymerase chain reaction (PCR) and IL-6 secretion in the culture medium was measured by enzyme linked immunosorbent assay (ELISA) at different time points.

RESULTS

The expression of IL-6 mRNA and the release of IL-6 were increased significantly in VSMC as early as 3 hours after being treated with LPS [mRNA: (21.3+/-3.2)x10(4), protein: (296.2+/-19.6) ng/L], peaked in 12 hours [mRNA: (131.4+/-11.2)x10(4), protein: (897.7+/-34.0) ng/L], and the elevation persisted up to 24 hours after treatment [mRNA: (15.3+/-4.7)x10(4), protein: (194.3+/-24.0) ng/L] compared with control group [mRNA: (9.4+/-1.9)x10(4), protein: (29.4+/-4.4) ng/L, all P<0.05]. On the other hand, the expression of IL-6 was significantly suppressed by p38MAPK inhibitor SB203580 at 3, 6, 12 hours [mRNA: (15.4+/-3.6)x10(4), (43.2+/-6.6)x10(4), (56.2+/-5.5)x10(4), protein: (180.3+/-23.6), (432.2+/-56.8), (546.2+/-57.9) ng/L, all P<0.05].

CONCLUSION

The release of IL-6 and the expression of IL-6 mRNA was increased significantly in LPS-challenged VSMC; however, the induction of IL-6 was significantly suppressed by p38MAPK inhibitor. p38MAPK may play an important role in the release of IL-6 induced by LPS.