Comparison of whole blood indium and the serum indium of the population exposed to the indium / 中华劳动卫生职业病杂志

Objective@#The method was established for the detection of whole blood indium and serum indium. By comparing the results of two samples, it is possible to explore the significance of whole blood indium and serum indium in the population exposed to indium compounds.@*Methods@#According to GBZ/T 295-2017 and GBZ 294-2017, the whole blood and serum samples were diluted 20 times by 0.5% nitric acid solution (including 0.05% Triton X-100) . Under the standard mode of inductively coupled plasma mass spectrometry (ICP-MS) , whole blood indium and serum indium of indirect exposure group, low exposure group and high exposure group in an indium mine were detected with 20 μg/L rhodium standard solution as internal standard.@*Results@#This method has a working range of 0.00~5.00 μg/L and a correlation coefficien t>0.999. The detection limit and quantitative lower limit of whole blood indium were 0.076 μg/L and 0.26 μg/L respectively. Those of serum indium were 0.06 μg/L and 0.20 μg/L accordingly. The recovery rates of serum and whole blood samples were 88.5%~95.6% and 93.0%~101%. Intra batch precisions were 1.3%~4.4% and 1.9%~3.5% and inter batch precision were 2.4%~6.1% and 2.1%~4.6% in two samples. There were no significant differences between whole blood indium and serum indium in indirect exposure group. The serum indium level was lower than the detection limit in 3 cases, while their whole blood indium was only below the quantitative lower limit. However, in other groups whole blood indium level was significantly higher than serum indium level (P<0.05) and even was two-fold in the high exposure group.@*Conclusion@#The detection of whole blood indium is more sensitive than that of serum indium, which can reflect the internal exposure level more accurately in exposure population. Therefore, the whole blood indium is of more important referential value to health examination and poisoning diagnosis in the population exposed to indium and its compounds.

The bifunctional effect of propofol on thromboxane agonist (U46619)-induced vasoconstriction in isolated human pulmonary artery

Propofol is known to cause vasorelaxation of several systemic vascular beds. However, its effect on the pulmonary vasculature remains controversial. In the present study, we investigated the effects of propofol on human pulmonary arteries obtained from patients who had undergone surgery. Arterial rings were mounted in a Multi-Myograph system for measurement of isometric forces. U46619 was used to induce sustained contraction of the intrapulmonary arteries, and propofol was then applied (in increments from 10–300 µM). Arteries denuded of endothelium, preincubated or not with indomethacin, were used to investigate the effects of propofol on isolated arteries. Propofol exhibited a bifunctional effect on isolated human pulmonary arteries contracted by U46619, evoking constriction at low concentrations (10–100 µM) followed by secondary relaxation (at 100–300 µM). The extent of constriction induced by propofol was higher in an endothelium-denuded group than in an endothelium-intact group. Preincubation with indomethacin abolished constriction and potentiated relaxation. The maximal relaxation was greater in the endothelium-intact than the endothelium-denuded group. Propofol also suppressed CaCl₂-induced constriction in the 60 mM K⁺-containing Ca²⁺-free solution in a dose-dependent manner. Fluorescent imaging of Ca²⁺ using fluo-4 showed that a 10 min incubation with propofol (10–300 µM) inhibited the Ca²⁺ influx into human pulmonary arterial smooth muscle cells induced by a 60 mM K⁺-containing Ca²⁺-free solution. In conclusion, propofol-induced arterial constriction appears to involve prostaglandin production by cyclooxygenase in pulmonary artery smooth muscle cells and the relaxation depends in part on endothelial function, principally on the inhibition of calcium influx through L-type voltage-operated calcium channels.

Dexmedetomidine inhibits vasoconstriction via activation of endothelial nitric oxide synthase

Despite the complex vascular effects of dexmedetomidine (DEX), its actions on human pulmonary resistance arteries remain unknown. The present study tested the hypothesis that DEX inhibits vascular tension in human pulmonary arteries through the endothelial nitric oxide synthase (eNOS) mediated production of nitric oxide (NO). Pulmonary artery segments were obtained from 62 patients who underwent lung resection. The direct effects of DEX on human pulmonary artery tension and changes in vascular tension were determined by isometric force measurements recorded on a myograph. Arterial contractions caused by increasing concentrations of serotonin with DEX in the presence or absence of L-NAME (endothelial nitric oxide synthase inhibitor), yohimbine (α2-adrenoceptor antagonist) and indomethacin (cyclooxygenase inhibitor) as antagonists were also measured. DEX had no effect on endothelium-intact pulmonary arteries, whereas at concentrations of 10⁻⁸~10⁻⁶ mol/L, it elicited contractions in endothelium-denuded pulmonary arteries. DEX (0.3, 1, or 3×10⁻⁹ mmol/L) inhibited serotonin-induced contraction in arteries with intact endothelium in a dose-dependent manner. L-NAME and yohimbine abolished DEX-induced inhibition, whereas indomethacin had no effect. No inhibitory effect was observed in endothelium-denuded pulmonary arteries. DEX-induced inhibition of vasoconstriction in human pulmonary arteries is mediated by NO production induced by the activation of endothelial α₂-adrenoceptor and nitric oxide synthase.

Dexmedetomidine inhibits 5-HT-induced intrapulmonary artery vasoconstriction / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of dexmedetomidine on 5-HT-induced constrictions of isolated human intrapulmonary arteries and explore the mechanisms.</p><p><b>METHODS</b>Lung tissue was obtained from patients undergoing surgery for lung carcinoma. Intrapulmonary arteries were dissected and cut into rings, which were mounted in a Multi Myograph system to determine the effect of dexmedetomidine (0.3-3 nmol/L) on 5-HT-induced vasoconstrictions. The influences of the endothelium removal and various drugs including L-NAME, yohimbine and indomethacin were tested on the effects of dexmedetomidine.</p><p><b>RESULTS</b>Dexmedetomidine (0.1-100 nmol/L) did not obviously affect the resting tension of endothelium-intact human intrapulmonary arteries. 5-HT induced concentration-dependent contraction in endothelium-intact intrapulmonary arteries [pD2: 6.11∓0.05, Emax: (102.10∓1.96)%]. In the rings with intact endothelium, dexmedetomidine (0.3-3 nmol/L) significantly attenuated the Emax and pD2 of 5-HT-induced vasoconstriction [pD2: 5.94∓0.03, Emax: (79.96∓1.31)%]. 5-HT also induced concentration-dependent contraction in endothelium-denuded intrapulmonary arteries [pD2: 6.10∓0.07, Emax: (107.40∓3.20)%]. Dexmedetomidine produced no significant effects on the rings with denuded endothelium. The effects of dexmedetomidine on 5-HT-induced vasoconstriction was suppressed by L-NAME and yohimbine, but not by indomethacin.</p><p><b>CONCLUSION</b>Dexmedetomidine can inhibit 5-HT-induced vasoconstriction of isolated human intrapulmonary arteries probably through α2-adrenergic acceptor and NO released from the endothelium.</p>

Role of parecoxib in protection of learning and memory ability in rats with transient global cerebral ischemia/reperfusion inj ury / 实用医学杂志

Objective To explore the role of parecoxib in protection of learning and memory ablility in rats with global cerebral ischemia/reperfusion injury. Methods Male Wistar rats were randomly divided into a sham group (S group), a ischemia/reperfusion group (I/R group), and a ischemia/reperfusion with parecoxib group (I/R+PA group). Global cerebral ischemia was induced by Pulsinelli 4-vessel occlusion. 72 h after reperfusion, Morris water maze was used to assess spatial learning and memory ability for consecutive five days. The histological changes in the hippocampus were detected by Nissl staining. Results As compared with the I/R group, rats in S guoup and I/R+PA group had a significantly shortened escape latency (P<0.05), and had significantly longer dwelling time in the former platform quadrant and more frequent cross-platform movement in the Morris water maze test. Conclusions Parecoxib plays a role in protection of learning and memory ability in rats with global cerebral ischemia/reperfusion injury.

Operation for postoperative re-hemorrhage after splenectomy with periesoph-agogastric devascularization for advanced schistosomiasis / 中国血吸虫病防治杂志

Objective To evaluate the efficacy of the operation in the treatment of postoperative re-hemorrhage after splenec-tomy with periesophagogastric devascularization for advanced schistosomiasis. Methods Forty-three re-hemorrhage patients,who received varicose ligation combined with pericardial devascularization through left thoracic cavity with esophageal incision from Oc-tober 2002 to October 2011,after splenectomy with periesophagogastric devascularization due to portal vein hypertension,were in-vestigated retrospectively and followed up for 1 to 9 years. Results Forty-three re-hemorrhage patients operated included 27 cas-es of selective operation and 16 cases of emergency operation. The mean follow-up time was 6.8 years. The hemostasis rate was 100%. 0ne died after the operation because of engaging in heavy labor,two had melena and were completely relived with the con-servative treatment,and all the rest had a good recovery. Conclusion The operation of varicose ligation combined with pericardi-al devascularization through left thoracic cavity with esophageal incision in the treatment of postoperative re-hemorrhage after sple-nectomy with periesophagogastric devascularization for advanced schistosomiasis has a satisfied efficacy.

The Relaxant Effect of Propofol on Isolated Rat Intrapulmonary Arteries

Propofol is a widely used anesthetic. Many studies have shown that propofol has direct effects on blood vessels, but the precise mechanism is not fully understood. Secondary intrapulmonary artery rings from male rats were prepared and mounted in a Multi Myograph System. The following constrictors were used to induce contractions in isolated artery rings: high K+ solution (60 mmol/L); U46619 solution (100 nmol/L); 5-hydroxytryptamine (5-HT; 3 micromol/L); or phenylephrine (Phe; 1 micromol/L). The relaxation effects of propofol were tested on high K+ or U46619 precontracted rings. Propofol also was added to induce relaxation of rings preconstricted by U46619 after pretreatment with the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME). The effects of propofol on Ca2+ influx via the L-type Ca2+ channels were evaluated by examining contraction-dependent responses to CaCl2 in the absence or presence of propofol (10 to 300 micromol/L). High K+ solution and U46619 induced remarkable contractions of the rings, whereas contractions induced by 5-HT and Phe were weak. Propofol induced dose-dependent relaxation of artery rings precontracted by the high K+ solution. Propofol also induced relaxation of rings precontracted by U46619 in an endothelium-independent way. Propofol at different concentrations significantly inhibited the Ca2+-induced contractions of pulmonary rings exposed to high K+-containing and Ca2+-free solution in a dose-dependent manner. Propofol relaxed vessels precontracted by the high K+ solution and U46619 in an endothelium-independent way. The mechanism for this effect may involve inhibition of calcium influx through voltage-operated calcium channels (VOCCs) and receptor-operated calcium channels (ROCCs).

Reactivity of intrapulmonary arterial rings to thromboxane A2 and endothelin-1 is reduced in patients with chronic obstructive pulmonary disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the reactivity of intrapulmonary arterial rings to vasoactive substances as thromboxane A2 and endothelin-1 in patients with chronic obstructive pulmonary disease (COPD).</p><p><b>METHODS</b>Intrapulmonary arterial rings isolated from patients with normal lung function and COPD were mounted in a Multi Myograph system to determine the reactivity of the intrapulmonary arterial rings to 60 mmol/L KCl, thromboxane A2 analogue U46619 and endothelin-1 before and after preconditioning with the COX synthase inhibitor indomethacin.</p><p><b>RESULTS</b>The reactivity of intrapulmonary arterial rings to U46619 and endothelin-1 was significantly decreased in patients with COPD. The reactivity to U46619 was dramatically decreased in patients with normal lung function after application of indomethacin.</p><p><b>CONCLUSION</b>The reactivity of intrapulmonary arterial rings is significantly decreased in patients with COPD.</p>

Effect of acute hypoxia on contractile function of isolated small pulmonary arteries in patients with moderate chronic obstructive pulmonary disease / 中华麻醉学杂志

Objective To evaluate the effect of acute hypoxia on the contractile function of isolated small pulmonary arteries in patients with moderate chronic obstructive pulmonary disease (COPD).Methods Seven patients with lung cancer,of both sexes,scheduled for elective pulmonary lobectomy,with no pulmonary hypertension and with normal pulmonary function after examination,were included in the study.Six cases were diagnosed as having moderate COPD.Lung tissues 5 cm away from the tumor tissues were taken during operation and the small pulmonary arteries were isolated and divided into 2 groups:control group (n =7) and COPD group (n =6).The contractile amplitude of small pulmonary arteries was detected using vasomotor tone meter under the state of acute hypoxia.Results Contractile amplitude of small pulmonary arteries in response to hypoxic stimulus was significantly decreased in COPD group compared with control group (P ＜ 0.01).Conclusion Acute hypoxia can further reduce the contractile function of isolated small pulmonary arteries in patients with moderate COPD.

Influence of washable type subglottic attract on incidence of ventilator- associated pneumonia in patients with mechanical ventilation / 中国实用护理杂志

ObjectiveTo explore the influence of washable type subglottic attract on incidence of ventilator-associated pneumonia (VAP) in patients with mechanical ventilation. Methods356 cases in need of mechanical ventilation from July 2009 to July 2010 in our hospital were chosen as the research object.They were randomly divided into the observation group and the control group with 178 cases in each group.The control group was treated with conventional endotracheal tube for mechanical ventilation.The observation group used washable type subglottic endotracheal tube to attract for mechanical ventilation.The VAP rate for the two groups occurred during mechanical ventilation in ventilator was compared.Migration of the dominant bacteria of the subglottic secretion was detected,underwent pathogenic examination and drug sensitivity test. ResultsThe VAP rate was significantly lower in the observation group than that of the control group.186 bacteria strains were detected from subglottic secretion,and 169 were detected from lower respiratory tract. ConclusionsWashable type subglottic attract for mechanical ventilation can reduce the risk of ventilator-associated pneumonia for patients with mechanical ventilation significantly,and it is worthy of clinical application.

Quantitive evaluation of the affective characteristic of Chinese words / 中华行为医学与脑科学杂志

Objective To understand affective characteristic of Chinese words. Method 1300 adjectives and nouns of Chinese words were rated in five point scale by 65 participants in three dimensions: emotional valence,arousal and familiarity. Results Neither age effect nor gender effect were found for the word scores in each scale of each dimension. The correlation coefficients between each two dimensions were significant (P＜0.01):0. 787 for valence-arousal, 0. 550 for valence-familiarity and 0. 600 for arousal-familiarity.Conclusion The affective vocabulary system of Chinese words can be used as a tool in future emotional research.