Concordant systemic and local eosinophilia relates to poorer disease control in patients with nasal polyps / 中华耳鼻咽喉头颈外科杂志

Objective: To explore whether blood and polyp tissue eosinophil numbers are independent risk factors for poor disease control in patients with nasal polyp. Methods: By using the electronic medical records database and manual evaluation, 183 nasal polyp patients who had undergone endoscopic sinus surgery at least one year prior to the study with complete data of tissue specimens, baseline blood routine test, nasal endoscopy and sinus computed tomography, were identified and recruited to assess disease control based on the criteria of a European Position Paper on Rhinosinusitis and Nasal Polyps 2012 (EPOS 2012). Multiple logistic regression model was used to determine the association between blood and tissue eosinophil numbers and risk of poor disease control by adjusting for demographics and comorbidities. Results: We broke down the cohort into 4 groups according to blood (0.3×109/L) and tissue (10%) eosinophils. The patients without eosinophilic inflammation represented the largest group (41.5%). The group with concordant blood and tissue eosinophilia represented the second largest (31.2%), and the patients with isolated tissue (15.3%) or blood (12.0%) eosinophilia were relatively rare. Multiple logistic regression models found blood eosinophil count and tissue eosinophil percentage were independently associated with increased risk for poor disease control after adjustments for covariates related to poor treatment outcome. Furthermore, subjects with concordant blood and tissue eosinophilia had a higher risk for poor disease control than those with isolated blood or tissue eosinophilia. Conclusion: Concordant blood and tissue eosinophilia relates to a higher likelihood of poor disease control than isolated blood or tissue eosinophilia after adjustment of potential confounders in nasal polyp patients.

Pathophysiological changes in mitochondria of mammalian exposed to hypoxia at high altitude / 中国应用生理学杂志

As human beings ascend to high altitude, a number of reactions may occur against hypoxic injuries. These hypoxic responses are related to intake, transportation and utility of the oxygen. As a crucial subcellular organelle of oxygen utility, mitochondrion is a central link of high altitude acclimatization, adaptation and mountain sicknesses. In this review, we discussed the recent advances in researches on hypoxic mitochondrial responses at high altitude.

Effects of hypoxia on ET and NO levels in cultured umbilical venous endothelial cells of native Tibetan / 中国应用生理学杂志

<p><b>AIM</b>To assay ET and NO in venous blood of native Tibetan and to investigate the effects of hypoxia on ET and NO levels in cultured umbilical venous endothelial cells of native Tibetan.</p><p><b>METHODS</b>ET and NO in venous blood of native Tibetan, immigrant Han and lowland Han were assayed. Umbilical venous endothelial cells (UVECs) from native Tibetan and immigrant Han newborns were cultured and divided into 4 groups: (1) Native Tibetan control group (TC), (2) Native Tibetan hypoxic group (TH), (3) Immigrant Han control group (HC), (4) Immigrant Han hypoxic group (HH). Supernatant was collected and ET and NO were detected.</p><p><b>RESULTS</b>Venous blood NO was significantly higher in native Tibetan than in immigrant Han, while ET lower in native Tibetan than in immigrant Han. ET excretion from UVECs was elevated while NO decreased in both Tibetan and Han groups after exposed to hypoxia. On time-points 12 h and 24 h, ET was significantly lower in TH than in HH, while concentration of NO showed no difference in TH and HH.</p><p><b>CONCLUSION</b>ET released by UVECs was higher in Han than in Tibetan after 12 h and 24 h hypoxic exposure, which may be in favor of lower vascular resistance and better fetal blood supply in Tibetan, and thus plays a role in the mechanisms of less intrauterine growth restriction (IUGR) throughout pregnancy and heavier birth weight of Tibetan newborns.</p>

Effects of hypoxia combined-exercise on blood viscosity and cardiac function of rats / 中国应用生理学杂志

<p><b>AIM</b>To study the effects of hypoxia alone or combined-exercise on blood viscosity and cardiac function of rats.</p><p><b>METHODS</b>22 wistar rats were divided into 3 groups: I normoxic control; II hypoxia and III hypoxia-combined exercise. Rats of II and III groups were subjected to hypobaric hypoxia for 5 weeks (23 h/day). They were first brought to simulated 4 000 m altitude, where rats of the III group were forced to swim for 1 h/day (6 days/week). Then the animals were ascent to 5 000 m. Cardiac function were detected by polygraph, the blood viscosity was assayed by E-viscosimeter, 99mTc radiolabelled frog red blood cell was used to measure the cardiac output.</p><p><b>RESULTS</b>Hypoxia alone caused an increase in blood hematocrit (Hct) and viscosity. Cardiac function of the left and right ventricles, especially +/- dp/dt(max) was also increased. Hypoxia-combined-exercise did not cause further increase in Hct, while the blood viscosity was decreased. Cardiac function increased further in both ventricles and the cardiac output was increased by 20% after hypoxia-combined-exercise.</p><p><b>CONCLUSION</b>During acclimatization to hypoxia, moderate exercise can decrease the blood viscosity and increase the cardiac function. These changes may be advantageous in delivering oxygen to tissues and may be favorable for promoting acclimation to high altitude.</p>

Effect of hypoxia on expression of iNOS mRNA in cultured rat astrocytes / 中国应用生理学杂志

<p><b>AIM</b>To explore the effects of hypoxia on expression of inducible nitric oxide synthase (iNOS) mRNA in cultured rat astrocytes.</p><p><b>METHODS</b>Cultured rat astrocytes were randomly divided into 4 groups: glutamate group (G), hypoxic group (H), hypoxia + glutamate group (H + G) and the control (C). Cells of control group were exposed to normoxic (95% air, 5% CO2) condition, and cells of G and H + G were incubated with 100 micromol/L L-glutamate, cells of H and H + G exposed to hypoxic conditions (5% CO2, 95% N2) at 37 degrees C. Each group had five timepoints which included 0 h, 3 h, 6 h, 12 h, 24 h, respectively. Expression of mRNAs of iNOS were detected with reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Expression of iNOS mRNA was not detectable in G and C, while it increased dramatically and continuously from 6 h to 24 h in H and G + H. Expression of iNOS mRNA was significantly higher in H than both in G and C at 6 h, 12 h and 24 h, and expression of iNOS mRNA was the highest of all groups in G + H.</p><p><b>CONCLUSION</b>Hypoxia upregulates the expression of iNOS mRNA in cultured astrocytes. Glutamate does not induce the expression of iNOS mRNA but enhance the effect of hypoxia, which is maybe one of the adaptive mechanisms of hypoxia-induced cerebral dilation.</p>

Effects of ATP concentration and hypoxic exposure on RNA and protein synthesis activity in isolated mitochondria from rat brain / 生理学报

To explore the effects of ATP concentration in the medium and hypoxia exposure on mitochondrial DNA expression at transcriptional and translational level, rats were exposed to hypoxia in a hypobaric chamber simulating 4000 m above sea level for 3 d (acute hypoxia) or 40 d (chronic hypoxia). Cerebral cortex mitochondria were isolated from control and hypoxia-exposed rats by centrifugation program. The activities of intramitochondrial RNA and protein synthesis were measured respectively by the methods of incorporation of (3)H-UTP or (3)H-Leucine in a cell-free system in vitro in isolated organelle. The effect of different ATP concentrations in medium on incorporation activity of mitochondria from control rat brains was observed. The results showed that there was a 40% reduction in RNA synthesis and a 60% inhibition in protein synthesis in isolated mitochondria in vitro in acute hypoxia exposure compared to control. But in chronic hypoxic exposure, the inhibition of both RNA synthesis and protein synthesis was alleviated, being 72% and 76% of the normoxic control, respectively. Furthermore, the effect of ATP concentration in medium on mitochondrial RNA and protein synthesis in vitro showed two phases. The mitochondrial RNA and protein synthesis were inhibited when ATP concentration was either above or below 1 mmol/L in the incubation medium. These results indicate that hypoxia exposure affects the expression of mtDNA at both transcription and translation levels. It also suggests that the improvement of mitochondrial semi-automation during chronic hypoxic exposure may be at least one of the cellular mechanisms of body adaptation to hypoxia. The regulation of ATP in mitochondrial RNA and protein synthesis is therefore an economic and effective mode of regulation.