[Effect of LIPUS on the cellular behavior of human primary macrophages].

AIM: To explore the effect of low intensity pulsed ultrasound (LIPUS) on the biological behavior of macrophages to provide some theoretical foundations for its clinical application. METHODS: Human primary macrophages were obtained by using modified Ficoll-paque density gradient centrifugation combined with adherent method. The phagocytosis of macrophages was analyzed using fluorescein-labelled E.coli. The expression of the secreted proteins was determined by proteins array and the secretion of metalloproteinases (MMPs) was examined by gelatin zymography. The focal complexes and extracellular matrix metalloproteinase inducer (CD147) were detected by fluorescence microscopy and the phosphorylation of Src and ERKs was examined by Western blot. RESULTS: The human primary macrophages were successfully isolated and cultured in vitro. LIPUS accelerated the macrophages to phagocytose E.coli, promoted the protein expression of CD147 and MMPs, increased the level of protein tyrosine phosphorylation, and induced the formation of focal complexes and the phosphorylation of Src and ERKs. CONCLUSION: LIPUS may up-regulate the phagocytosis and secretion of human primary macrophages through the activation of Src and ERKs.

[Molecular mechanisms of low intensity pulsed ultrasound-mediated cellular behavior in human primary macrophages].

The aim of this study was to explore the molecular mechanisms of the effect of low intensity pulsed ultrasound (LIPUS) on human primary macrophage functions. Macrophage phagocytosis was analyzed using fluorescein isothiocyanate (FITC)-labelled Escherichia coli (E.Coli); focal complex and extracellular matrix metalloproteinase inducer (EMMPRIN) were observed by fluorescence microscopy; the secretion of metalloproteinases (MMPs) was examined by gelatin zymography, and the expressions of EMMPRIN and extracellular signal-regulated kinases (ERKs) were detected by Western blot. The results indicated that LIPUS accelerated macrophages to phagocytose E.Coli (29.81+/-0.36 vs 18.00+/-0.78), promoted the protein expressions of EMMPRIN and MMPs, increased the level of protein tyrosine phosphorylation, and induced the phosphorylation of ERKs. Furthermore, the above functions were only found in adherent macrophages, and were inhibited or decreased by mitogen activated protein kinase kinase (MAPK kinase, MEK) inhibitor PD98059 and RGD (Arg-Gly-Asp peptide), one of main integrin recognition sequences. It is concluded that the effect of LIPUS on macrophages depends on cell adhesion, and relates to integrin-MEK-ERK pathway.

Identification of quantitative trait loci controlling drought tolerance at seedling stage in Chinese Dongxiang common wild rice (Oryza rufipogon Griff.).

Common wild rice (Oryza rufipogon Griff.) is the ancestor of cultivated rice (O. sativa L.), which has a greater genetic diversity and important traits that remain to be employed in cultivated rice. In this study, a set of introgression lines (BC4F5 and/or BC4F6) carrying various introgressed segments from common wild rice, collected from Dongxiang county, Jiangxi Province, China, in the background of an Indica (O. sativa L. ssp. indica) cultivar, Guichao 2, was used. A total of 12 drought-related quantitative trait loci (QTL) were identified by investigating drought tolerance of introgression lines under 30% PEG treatment at the young seedlings stage. Of these QTLs, the alleles of 4 QTLs on chromosome 2, 6 and 12 from Dongxiang common wild rice were responsible for increased drought tolerance of the introgression lines. In particular, a QTL qSDT12-2, near RM17 on chromosome 12, was consistently detected in different replications, and expressed stably under PEG stress throughout the study. It was also found that the QTLs located on different chromosomes might express at different stages.

[Effect of sustained inflation on inflammatory response of extra pulmonary organs in acute respiratory distress syndrome in rabbit].

OBJECTIVE: To evaluate the influence of sustained inflation (SI) on inflammatory response of extra pulmonary organs in acute respiratory distress syndrome (ARDS) in rabbit. METHODS: The ARDS rabbit model were replicated by saline alveoli-lavage. The rabbits were randomly divided into four groups: 1. normal group; 2. ARDS group; 3. low-volume(V(T)) + best end-expiratory pressure group (LVBP): V(T) 6 ml/kg, PEEP 2 cm H(2)O(1 cm H(2)O=0.098 kPa) greater than the pressure of lower inflection point in pressure-volume curve (Pinf); 4. SI group: same settings as LVBP group plus SI performed every hour. After 4 hours of ventilation, liver and intestine homogenates were prepared to assay tumor necrosis factor (TNF)-alpha and interleukin(IL)-10 levels by enzyme-linked immunoadsorbent assay and their mRNA expression by reverse transcription-polymerase chain reaction. Myeloperoxidase (MPO) and malondialdehyde (MDA) were assessed at the same time. RESULTS: In SI group, TNF-alpha mRNA expression in the liver and intestine tissues (24.82+/-7.88 and 25.06+/-10.57) were decreased significantly compared with ARDS (36.88+/-6.83 and 36.48+/-8.23) and LVBP groups (42.34+/-8.55 and 37.59+/-10.63, all P<0.05). The expression of IL-10 mRNA in the liver and intestine of rabbits in SI group (17.31+/-5.72 and 10.90+/-3.30) was lower than that of ARDS (24.64+/-3.85 and 24.31+/-7.69) and LVBP group (25.03+/-9.38 and 21.83+/-7.34, all P<0.05) significantly. In SI group, the levels of TNF-alpha and IL-10 in liver and intestine tissue were similar to that of the other groups. The contents of MPO and MDA had no difference compared with the other groups too. CONCLUSION: SI can down-regulate inflammatory mediator expression of extra-pulmonary organs in rabbits with ARDS, and it may inhibit the inflammatory response in extra pulmonary organs.

[Effects of positive end-expiratory pressure on lung recruited volume and oxygenation in patients with acute respiratory distress syndrome].

OBJECTIVE: To access alveolar recruitment with positive end-expiratory pressure (PEEP) and to correlate the recruited volume with arterial oxygenation in acute respiratory distress syndrome (ARDS). METHODS: Eleven ventilated patients satisfying criteria of ARDS were included in the study group. Recruited volume of three different PEEP levels [5 cm H2O, 10 cm H2O, 15 cm H2O (1 cm H2O=0.098 kPa)] were measured by pressure-volume curve method. Effects of different PEEP levels on lung mechanics and gas exchange were compared. RESULTS: Lung recruited volume elevated when PEEP increased from 5 cm H2O to 15 cm H2O[(40.2+/-15.3)ml vs. (123.8+/-43.1)ml vs. (178.9+/-43.5)ml, all P<0.05]. Arterial oxygenation index increased with PEEP and a positive correlation was found between recruited volume and changes in arterial oxygenation index (r=0.483, P<0.01). There was no significant difference during the static compliance at different PEEP levels at a fixed tidal volume (P>0.05). Recruited volume at PEEP 15 cm H2O in the patient group with lower inflection point (LIP) was larger than the group without LIP. CONCLUSION: Recruited volume increases with PEEP, and the PEEP-induced increase in arterial oxygenation is significantly correlated to recruited volume.

[A comparison study on quantitative methods for the recruited volume in sheep with acute respiratory distress syndrome].

OBJECTIVE: To compare equal pressure method with pressure-volume curve method to quantify the recruited volume. METHODS: Acute respiratory distress syndrome sheep model was induced by intravenous infusion 3 microg/kg lipopolysaccharide (LPS). Recruited volume of three different levels of positive end-expiratory pressure (PEEP=5, 10, 15 cm H2O) were measured both by pressure-volume curve method and by equal pressure method. RESULTS: The time needed to measure recruited volume by pressure-volume curve method was 5-6 minutes, which was longer than that of equal pressure method. Recruited volume measured by the two methods increased with PEEP. No significant difference was found between the recruited volume measured by equal pressure method and by equal pressure method at PEEP of 5 cm H2O, they were (25.79+/-20.48) ml vs. (63.26+/-54.57) ml (P>0.05), while recruited volume at PEEP of 10 cm H2O and 15 cm H2O measured by equal pressure method were lower than those measured by the pressure-volume curve method, they were (48.64+/-30.51)ml vs. (148.14+/-85.42)ml and (71.50+/-58.09)ml vs. (322.86+/-148.42)ml (all P<0.05) respectively. CONCLUSION: Though equal pressure method is simple, it could not take the place of pressure-volume curve method to quantify recruited volume.

[Effect of lung protective ventilation strategy on pulmonary inflammatory response in a rabbit model of acute respiratory distress syndrome].

OBJECTIVE: To evaluate the effect of lung protective ventilation strategy on pulmonary inflammatory response in acute respiratory distress syndrome (ARDS). METHODS: The ARDS rabbit model was duplicated by saline alveolar-lavage. The rabbits were divided into six groups: (1) normal control group (N group); (2) ARDS group (M group); (3) low-volume with best end-expiratory pressure (PEEP, A group) group: tidal volume (V(T)) 6 ml/kg, PEEP 2 cm H(2)O greater than the pressure of lower inflection point in pressure-volume curve (P(LIP)); (4) normal-volume with best PEEP group (B group): V(T) 6 ml/kg, and PEEP P(LIP) + 2 cm H(2)O; (5) low-volume with high PEEP group (C group): V(T) 6 ml/kg, and PEEP 15 cm H(2)O; and (6) high-volume with zero PEEP group (D group): V(T) 20 ml/kg. Lung wet/dry weight ratios (W/D) were recorded to evaluate lung injury. After 4 h of ventilation, lung homogenates were prepared to detect nuclear factor-kappaB (NF-kappaB) activity by electrophoretic mobility gel shift assay (EMSA), tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) levels by enzyme-linked immunosorbent assay (ELISA) and their mRNA expression by reverse transcriptase-polymerase chain reaction (RT-PCR). Myeloperoxidase (MPO) and malondialdehyde (MDA) in lung homogenates were also assessed. RESULTS: After 4 h ventilation, W/D in A group (5.6 +/- 1.1) were significantly lower than those in B group, C group and D group (6.6 +/- 0.8, 6.6 +/- 1.0, 6.9 +/- 1.0, all P < 0.05). But there was no difference between A group and M group (5.8 +/- 0.5). NF-kappaB activity was the highest in D group, and that in A group was 331 +/- 113, which was decreased significantly as compared with B, C and D groups (455 +/- 63, 478 +/- 74, 645 +/- 162, all P < 0.05). The mRNA expression of TNF-alpha and IL-10 and their concentrations in lung homogenates in A group were lower than those in B, C and D groups. In A group, the concentrations of MPO and MDA in lung homogenates were significantly lower than those in B, C and D groups. CONCLUSION: Lung protective ventilation strategy can inhibit lung inflammation and may improve lung injury in ARDS, but low tidal volume with high PEEP may increase lung inflammation.

[Comparison of effect of norepinephrine-dobutamine and that of dopamine alone on splanchnic perfusion in sheep with septic shock].

OBJECTIVE: To compare the effect of norepinephrine-dobutamine and that of dopamine alone on splanchnic perfusion in sheep with septic shock. METHODS: Twenty sheep with septic shock induced by lipopolysaccharides were divided into two groups. When systolic pressure was decreased to 39.75 mm Hg(1 mm Hg=0.133 kPa), basic values of hemodynamic parameters and intestinal intramucosal pH (pHi) were monitored. The animals were randomized to either receive an intravenous infusion of norepinephrine-dobutamine in combination or dopamine alone, and the dosage was titrated to obtain a mean arterial pressure (MAP)> 90.00 mm Hg with an optimal cardiac preload. Hemodynamic parameters and mucosal pHi were repeatedly measured at 1-, 2-, 3-, 4-hour after basic measurement. RESULTS: After norepinephrine-dobutamine or dopamine infusion, MAP, cardiac output, and oxygen delivery were increased in all animals compared to basic values in both groups (P<0.05). Compared to baseline values (4.0+/-1.8)mmol/L, lactate concentrations were decreased at 3-hour (2.3+/-1.1) mmol/L and 4-hour (2.1+/-1.1)mmol/L in the norepinephrine-dobutamine group (P<0.05). There were no differences in arterial lactate concentrations in the dopamine group, but arterial pH was decreased from 7.40+/-0.05 to 7.26+/-0.06 at 2-hour (P<0.05 ). No Change in pHi was found in the dopamine group, but in the norepinephrine-dobutamine group, compared to baseline, pHi was increased from 7.19+/-0.04 to 7.36+/-0.07 at 3-hour (P<0.05). CONCLUSION: Both norepinephrine-dobutamine and dopamine could improve systemic hemodynamics in sheep with septic shock, but the effect of norepinephrine-dobutamine in combination was better than dopamine on splanchnic perfusion.

Effects of norepinephrine, epinephrine, and norepinephrine-dobutamine on systemic and gastric mucosal oxygenation in septic shock.

AIM: To compare the effects of dopamine, norepinephrine, epinephrine, and the combination of norepinephrine and dobutamine on systemic and gastric mucosal oxygen metabolism in patients with septic shock. METHODS: Sixteen patients with septic shock were enrolled in the present study. Each patient received dopamine firstly, then in a random succession epinephrine, norepinephrine, or norepinephrine-dobutamine, a mean systemic arterial pressure adjusted to >9.31 kPa. After 120 min of each treatment, hemodynamic, oxygen metabolic, and gastric mucosal parameters were obtained. RESULTS: Epinephrine induced a significant increase in heart rate compared with other three groups (P <0.05), and a significant higher cardiac index compared with norepinephrine alone and norepinephrine-dobutamine (P <0.05). Oxygen extraction ratio values were lower with epinephrine infusion as compared with other three groups (P <0.05). Arterial lactate concentrations decreased significantly with norepinephrine-dobutamine as compared with dopamine and epinephrine infusions (P <0.05). As compared with epinephrine infusion, the gastric intramucosal pH values were higher with norepinephrine-dobutamine infusion (7.25+/-0.09 vs 7.14+/-0.07, P <0.05). CONCLUSION: Dopamine, norepinephrine, epinephrine, or norepinephrine-dobutamine improved blood pressure. Epinephrine and dopamine had deleterious effect on oxygen metabolism, while norepinephrine plus low dose of dobutamine improved gastric mucosal perfusion and tissue oxygen utilization.

Comparison of norepinephrine-dobutamine to dopamine alone for splanchnic perfusion in sheep with septic shock.

AIM: To compare the effect of norepinephrine-dobutamine with dopamine alone on splanchnic perfusion in sheep with septic shock. METHODS: Twenty sheep with septic shock induced by lipopolysaccharides were divided into two groups. When systolic pressure decreased by 5.3 kPa, basic values of hemodynamic parameters and intestinal intramucosal pH (pHi) were recorded. Each group was randomized to receive an intravenous infusion of norepinephrine-dobutamine or dopamine, and titrated to obtain mean arterial pressure (MAP) > 12 kPa with an optimal cardiac preload. Hemodynamic parameters and mucosal pHi were repeated at 1, 2, 3, and 4 h after basic measurement. RESULTS: After norepinephrine-dobutamine or dopamine infusion, MAP, cardiac output, and oxygen delivery increased in all animals compared with basic values in both groups (P < 0.05). Compared with baseline values, lactate concentrations decreased at 3 h and 4 h [from (4 +/- 2) mmol/L to (2 +/- 1) mmol/L] in the norepinephrine-dobutamine group (P < 0.05 ). Arterial lactate concentrations had no change in dopamine group, but arterial pH decreased from 7.40 +/- 0.05 to 7.26 +/- 0.06 at 1 h (P < 0.05 ). No difference in pHi was found in dopamine group, but in the norepinephrine-dobutamine group, compared with baseline, pHi increased from 7.19 +/- 0.04 to 7.36 +/- 0.07 at 3 h (P < 0.05). CONCLUSION: Both norepinephrine-dobutamine and dopamine alone could improve systemic hemodynamics in sheep with septic shock, but norepinephrine-dobutamine was better than dopamine on splanchnic perfusion.