[Timing of starting veno-venous extracorporeal membrane oxygenation]

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is mainly used for reversible acute respiratory failure that is difficult to correct with mechanical ventilation and other conventional measures or preparation of lung transplantation. Acute respiratory distress syndrome (ARDS) is a typical clinical syndrome of acute respiratory failure. The timing of starting VV-ECMO in severe ARDS still face many controversies and challenges. This paper we discuss the current feasible assessment methods of when to start VV-ECMO in ARDS, such as, optimization of mechanical ventilation parameters, monitoring of respiratory dynamics and hemodynamics, assessment of lung recruitability and electrical impedance tomography (EIT) real-time monitoring, etc.

[Effects of crystalline silica with different exposure patterns on lung fibrosis in rats]

Objective: To investigate the effects of crystalline silica with different exposure patterns on lung fibrosis in rats. Methods: A total of 20 adult male Wistar rats were randomly divided into 4 groups consisting of five animals each and received intratracheal instillation of sterile saline or silica suspension in different patterns: saline once at day 0, saline once/week, crystalline silica 50 mg at day 0, crystalline silica 6.25 mg/week. The rats were sacrificed at 8 weeks. The lung tissues were collected for pathological analyses, and determining mRNA and protein levels of related fibrogenic molecules. Results: The collagen deposition induced by crystalline silica in lung tissues were increased. The mRNA levels of IL-1β and Col I in group c were significantly elevated than those in group saline once at day 0 (all P<0.05). Compared with group saline once/week, the mRNA levels of IL-1β, TGF-β, Col I, Col III and CTGF were significantly increased in group crystalline silica 6.25 mg/week (P<0.05) . The mRNA levels of Col I and CTGF were significantly increased in group crystalline silica 6.25 mg/week in comparison with those in group crystalline silica 50 mg at day 0 (P<0.05) . Conclusion: Given the same cumulative dose of crystalline silica, multiple exposures were likely to induce more severe lung fibrosis.

Detection of serum procalcitonin and hypersensitive C-reactive protein in patients with pneumonia and sepsis

Sepsis, a systemic inflammatory response syndrome induced by infection, has high rates of morbidity and mortality. Pneumonia is a major cause for sepsis; however, pneumonia complicated by sepsis is a difficult clinical diagnosis. To assess the clinical relevance of serum procalcitonin (PCT) and hypersensitive C-reactive protein (hs-CRP) in early diagnosis of pneumonia complicated by sepsis, 220 patients with pneumonia who were admitted to hospital from July 2015 to July 2016 were enrolled in this study. The patients were divided into non-sepsis (N=82), mild sepsis (N=97), severe sepsis (N=23), and septic shock (N=18) groups. The patients were also divided into a survival group (N=186) and a death group (N=34) according to their prognosis at 2 weeks. The PCT and hs-CRP levels and Acute Physiology and Chronic Health Evaluation-II (APACHE-II) scores of the two groups were evaluated. The PCT level and APACHE-II score showed a progressively increasing tendency in the non-sepsis, mild sepsis, severe sepsis, and septic shock group; the differences between all pairs of groups were significant (P less than 0.05). The hs-CRP level was significantly lower in the non-sepsis group than in the other groups (P less than 0.05), but differences among the other groups were not significant (P>0.05). The areas under the receiver operating characteristic curves of PCT and hs-CRP for diagnosis of pneumonia complicated by mild and severe sepsis were 0.841 and 0.817, respectively. The optimal cut-off points for pneumonia and sepsis were ≥0.5 ng/mL and ≥55 mg/L, respectively; the sensitivity and specificity were 71.42% and 82.13%, and 75.04% and 53.61%, respectively. The sensitivity and specificity of diagnosis based on PCT and hs-CRP were 89.32% and 85.68%, respectively. PCT and hs-CRP are used to assess the severity of pneumonia in combination with sepsis in new-borns, but PCT is more strongly related to the severity of sepsis than is hs-CRP. Detection of PCT in combination with hs-CRP facilitates the early diagnosis of pneumonia and sepsis in new-borns, as well as monitoring of the treatment response and prediction of the prognosis.

[Effect of Gas6 in silica-induced inflammation on differentiated human acute monocytic leukemia (THP-1) macrophages]

Objective: To investigate the modulation role of Gas6 in silica-induced inflammatory effect on human macrophages. Methods: Differentiated THP-1 macrophages were exposed to different concentrations of silica for 6 h and 24 h. Additionally, silica-activated macrophages were treated with different concentrations of recombine human Gas6 and Gas6 antibody respectively. Cell viabilities were determined by CCK-8 kit. Expression levels of Gas6 and inflammatory cytokines (TNF-α, IL-1β and IL-6) were measured by ELISA assay kits. Results: Silica particles induced clear dose-dependent decreases of cell viability and Gas6 expression at both 6 h and 24 h. The cell viability of 24 h is lower than 6 h at the same concentration of silica (P<0.05). Furthermore, silica activated macrophages treated with Gas6 antibody induced significant decreases of Gas6 both at 6 h and 24 h (P<0.05). After pretreated with various concentrations of Gas6 antibody, silica induced higher expressions of inflammatory cytokines (TNF-α, IL-1β, IL-6) in dose-dependent manners at two time points. Addition of exoge-nous Gas6 significantly suppressed silica-induced inflammatory cytokines concentrations mentioned above in the cell culture supernatants in clear dose-dependent manners. Conclusion: Exogenous Gas6 could inhibit the secre-tion of inflammatory cytokines in macrophages, while the block of Gas6 might enhance this inflammation.

[Association of urinary metals and lung function in general Chinese population of Wuhan]

OBJECTIVE

To investigate the association between levels of 23 urinary metals and lung function, and explore their does-response relationships in the general population of Wuhan province, China.

METHODS

This was a cross-sectional study that enrolled volunteers from two communities of Wuhan between April and May 2011. All volunteers had resided in Wuhan for at least 5 years. Information from questionnaires and physical examinations were collected and lung function was assessed. Data from 2 540 volunteers were included. Urinary levels of 23 metals were measured by inductively coupled plasma mass spectrometry (ICP-MS). The relationship between urinary metals and lung function was analyzed with single and multiple regression models.

RESULTS

The mean age of the study population was 52.8 years. Mean levels of urinary metals, after adjustment for creatinine, including cobalt, copper, zinc, nickel, antimony and barium were 0.02, 0.68, 23.80, 0.20, 0.10, 0.34 and 0.26 μg/g creatinine, respectively. There were significant concentration-response relationships between increases in some urinary metals and reduced lung function. Single-metal regression models demonstrated that for each 1-unit increase in urinary levels of cobalt, lncopper, lnzinc, lnantimony, there was a reduction in forced vital capacity (FVC) of 0.091 L (95%CI: -0.155--0.027), 0.101 L (95%CI: -0.178--0.025), 0.094 L (95%CI: -0.172--0.027) and 0.118 L (95% CI: -0.203--0.033), respectively. Each 1-unit-increase in urinary lncobalt, lnnickel, lnstrontium, lnantimony, lnthallium, lnlead was associated with a reductions in forced expiratory volume in 1 sec (FEV1) of 0.070 L (95%CI: -0.124--0.016), 0.063 L (95%CI: -0.118--0.007), 0.063 L (95%CI: -0.124--0.002), 0.092 L (95%CI: -0.164--0.020), 0.055 L (95%CI: -0.105--0.005), 0.081 L (95%CI: -0.148--0.014), and 0.097 L (95% CI: -0.151--0.042), respectively. With respect to metal co-exposure, FVC was significantly associated with elevated urinary levels of cobalt, Cu and Sb, with reductions of 0.126 L (95%CI: 0.037-0.216) and 0.106 L (95% CI: 0.021-0.192), respectively, while FEV1 was significantly associated with elevated urinary Co, Sb, Ba and Pb, with reductions of 0.067 L (95% CI: -0.129--0.005), 0.142 L (95% CI: -0.247--0.037), 0.073 L (95% CI: -0.142--0.003) and 0.104 L (95% CI: -0.175--0.034), respectively.

CONCLUSIONS

Certain urinary metals were potentially associated, in a dose-dependent manner, with reduced lung function in the general population. Co-exposure to metals had stimulative and anti-stimulative effects on lung function.

[Association between personal exposure to metals in fine particulate matter and urinary metals: baseline results from a panel study]

OBJECTIVE

To investigate the associations between 21 metals in fine particulate matter (PM2.5) and their corresponding concentrations in urine in the general population.

METHODS

Between April and May 2011, this panel study enrolled 120 residents using random sampling approach in Wuhan communities which contained 3 035 subjects. Participants were aged 18 to 80 years and had lived in the sampling buildings for at least 5 years. Data from basic questionnaires, physical examinations, and morning blood and urine samples under fasting conditions were collected. Participants with missing data were excluded. Finally, 83 particpants included. Participants were instructed to use personal air samplers to continuously monitor PM2.5 for 24 h. The following 21 metals were measured in PM2.5 and urine by inductively coupled plasma mass spectrometry: aluminum, titanium, vanadium, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium, rubidium, strontium, molybdenum, cadmium, tin, antimony, barium, tungsten, thallium and lead. The associations between PM2.5 metals and urinary metals were investigated using generalized linear regression models.

RESULTS

The age of the study population was (51.5±6.3)years. After adjusting for age, sex, smoking status, BMI, education and income, elevated urinary chromium was significantly associated with increased chromium concentrations in personal PM2.5. The least square means (standard deviation) of urinary chromium in participants classified as having low exposure (<12.491 ng/m(3)), intermediate exposure (12.491-32.388 ng/m(3)) and high exposure (>32.388 ng/m(3)) were (-1.334±0.756), (-1.114±0.813) and (-0.718±0.645) μg/mmol creatinine, respectively (P=0.009). However, the association between urinary and personal PM chromium was not observed after additionally adjusting for false discovery rate (P>0.05). Furthermore, the results demonstrated that other metals in PM2.5 were not related to their corresponding concentrations in urine of subjects.

CONCLUSION

Urinary concentrations of metals did not reflect human exposure to metals in air, and may not be appropriate as an index to assess personal exposure to metals in particulate matter.

How important is the {103} plane of stable Ge2 Sb2 Te5 for phase-change memory?

Closely correlating with {200} plane of cubic phase, {103} plane of hexagonal phase of Ge(2)Sb(2)Te(5) plays a crucial role in achieving fast phase change process as well as formation of modulation structures, dislocations and twins in Ge(2)Sb(2)Te(5). The behaviors of {103} plane of hexagonal phase render the phase-change memory process as a nanoscale shape memory.

Toward structural/chemical cotailoring of phase-change Ge-Sb-Te in a transmission electron microscope

Ge2Sb2Te5, as the prototype material for phase-change memory, can be transformed from amorphous phase into nanoscale rocksalt-type GeTe provided with an electron irradiation assisted by heating to 520°C in a 1250 kV transmission electron microscope. This sheds a new light into structural and chemical cotailoring of materials through coupling of thermal and electrical fields.

Possible involvement of integrin signaling pathway in the process of recovery from restraint stress in rats

OBJECTIVE

To search novel genes or pathways involved in the recovery process after restraint stress in rats.

METHODS

We compared the hypothalamus transcriptional profiles of two different recovery patterns (fast recovery vs slow recovery) from restraint stress in rats using oligonucleotide microarray, the recovery pattern was determined by the decrement of plasma adrenocorticotropic-hormone (ACTH) and corticosterone levels during one hour recovery period after stress. A real-time quantitative RT-PCR was applied to validate the differential expressed genes.

RESULTS

Analysis of the microarray data showed that most of genes were not differentially expressed between fast recovery group and slow recovery group. Among the differentially expressed genes we found that talin, together with serine/threonine protein phosphatase PP1-beta catalytic subunit (PP-1B) and integrin alpha-6 precursor (VLA-6) genes, were at least 1.5 fold up-regulated in the fast recovery group, while junctional adhesion molecule 1 (F11r) was 1.5 fold down-regulated in the fast recovery group.

CONCLUSION

The results implied that integrin signaling pathway may be involved in the recovery from restraint stress in rats. The present study provided a global overview of hypothalamus transcriptional profiles during the process of recovery from the restraint stress in rats. The integrin signaling pathway seems to be involved in the recovery process, which deserves further study to clarify the integrin-mediated recovery mechanism after restraint stress.