Initial respiratory support modality and outcome in preterm infants with less than 32 weeks of gestation in China: A multicentre retrospective cohort study.

BACKGROUND: For initial respiratory management, continuous positive airway pressure (CPAP) is increasingly used for preterm infants, especially for gestational age less than 32 weeks. However, neonatologists are concerned about the potential risks of CPAP support failure. OBJECTIVES: To examine the association between different initial respiratory support modalities and the outcomes of preterm infants at <32 weeks of gestation across multiple neonatal intensive care units (NICU) in China. METHODS: This study was carried out over a period of 12 months in 2018. Unadjusted relative risks (RR) for demographic and clinical characteristics were calculated for CPAP failure and CPAP success in the total cohort using log-linear model based on generalised estimating equations for clustered observations. RESULTS: Among 1560 preterm infants delivered at <32 weeks, the incidence of CPAP failure was 10.3%. After adjustment for demographic and clinical factors, the relative risk of mortality (RR 7.54, 95% CI 5.56, 10.44), pneumothorax (RR 9.85, 95% CI 2.89, 61.53), pulmonary haemorrhage (RR 7.78, 95% CI 4.51, 14.64) and BPD (RR 3.65, 95% CI 3.65, 4.51) were considerably higher for infants in the CPAP failure group than those in the CPAP-S group. However, the risk of poor outcomes in CPAP failure infants was similar to that of those in the initial mechanical ventilation (MV) group. CONCLUSIONS: Continuous positive airway pressure failure was associated with an increased risk of mortality and major morbidities, including BPD, pulmonary haemorrhage and pneumothorax, and was comparable to the risk associated with initial MV.

Platelet-to-lymphocyte ratio is associated with prognosis in patients with coronavirus disease-19.

Since December 2019, novel coronavirus infected pneumonia emerged in Wuhan city and rapidly spread throughout China. In severe novel coronavirus pneumonia cases, the number of platelets, their dynamic changes during the treatment, platelet-to-lymphocyte ratio (PLR) were a concern. We sought to describe the platelet feature of these cases. Single-center case series of the 30 hospitalized patients with confirmed coronavirus disease (COVID)-19 in Huizhou municipal central hospital from January 2020 to February 2020 were retrospectively analyzed. Demographic, clinical, blood routine results, other laboratory results, and treatment data were collected and analyzed. Outcomes of severe patients and nonsevere patients were compared. Univariate analysis showed that: age, platelet peaks, and PLR at peak platelet were the influencing factors in severe patients, multivariate analysis showed that the PLR value at peak platelet during treatment was an independent influencing factor in severe patients. The average hospitalization day of patients with platelet peaks during treatment was longer than those without platelet peaks (P < .05). The average age of patients with platelet peaks during treatment was older than those without platelet peaks (P < .05). The patients with significantly elevated platelets during treatment had longer average hospitalization days. And the higher PLR of patients during treatment had longer average hospitalization days. Single-center case series of the 30 hospitalized patients with confirmed COVID-19 in Huizhou Municipal Central Hospital, presumed that the number of platelets and their dynamic changes during the treatment may have a suggestion on the severity and prognosis of the disease. The patient with markedly elevated platelets and longer average hospitalization days may be related to the cytokine storm. The PLR of patients means the degree of cytokine storm, which might provide a new indicator in the monitoring in patients with COVID-19.

[Effect of Active Ingredients of Qingxin Kaiqiao Recipe on Spatial Learning and Memory Capacities, and Expressions of Bax, Bcl-2, Caspase-3, and PAPP in Hippocampus of AD Model Rats].

Objective To observe the effects of active ingredients of Qingxin Kaiqiao Recipe (QKR) , such as saponins, volatile oils, effective compositions of polysaccharides, on expressions of Bcl-2 associated X protein (Bax) , B-cell lymphoma-2 (Bcl-2) , cysteinyl aspartate specific proteinase-3 (Caspase-3) , and ß-amyloid precursor protein (pAPP) in hippocampus of Ap1_40-induced Alzheimer's disease (AD) model rats. Methods Totally 112 male Sprague-Dawley (SD) rats were randomly divided into 7 groups, i.e., the normal control group, the sham-operation group, the model group, the Aricept group, the saponin group, the volatile oil group, the polysaccharide group, 16 in each group. The AD rat model was established by injecting Aß1₋40 from bilateral hippocampus. Equal volume of double distilled water was administered to rats by gastrogavage in the normal control group, the sham-operation group, the model group from the 2nd day after modeling, once per day for 2 successive weeks (at 10:00 am). Aricept (Donepezil Hydrochloride Tablet, 1. 67 mg/kg per day) , saponin (9 mL/kg per day) , benzene (3. 33 mL/kg per day) , and polysaccharides (8. 33 mL/kg per day) was administered to rats by gastro- gavage to the Aricept group, the saponin group, the volatile oil group, the polysaccharides group, re- spectively, once per day for 2 successive weeks (at 10:00 am). By the end of gastrogavage spatial learning and memory capacities were detected using Morris water maze (MWZ). Apoptosis in hippocam- pal CAI region was detected using TUNEL staining. Expressions of Bax, Bcl-2, Caspase-3, and PAPP were measured via Real-time fluorescent quantitative PCR, Western blot, and immunohistochemistry, respectively. Results There was no statistical difference in pre-modeling escape latency and times of crossing platforms among groups at the same time point (P >0. 05). Besides, escape latency was gradu- ally shortened as time went by. Compared with the model group, escape latency was shortened, and times of crossing platforms was significantly increased in the Aricept group and the saponin group (P < 0. 05, P <0. 01). Compared with the model group, the amount of apoptotic cells in hippocampal CA1 re- gion was obviously reduced (P <0. 05, P <0. 01) , expressions levels of Bax, Caspase-3, and pAPP were down-regulated, Bcl-2/Bax ratio was obviously elevated in the saponin group, the volatile oil group, the polysaccharide group (P <0. 05, P <0. 01). Conclusion Three active ingredients (spaonins, benzene, and polysaccharides) of QKR could improve spatial memory and learning capacities to different degrees, which might be possibly achieved by decreasing expressions of Bax, Caspase-3, PAPP in hippocampal CA1 region, elevating Bcl-2 expression, and inhibiting apoptosis in hippocampus.

[Study on the Mechanism of Three Kinds Extracts of Qingxin Kaiqiao Recipe in Improving Learning and Memory Capabilities of AD Rats].

OBJECTIVE: To explore the mechanism of three kinds extracts (saponins, volatile components, polysaccharide components) of Qingxin Kaiqiao Recipe (QKR) in improving learning and memory capabilities of Alzheimer's disease (AD) rats. METHODS: A controlled comparison method was used. Totally 56 male SD rats were randomly divided into seven groups, i.e., the normal control group, the sham-operation group, the model group, the Aricept group, the saponin group, the benzene group, and the polysaccharide group, 8 in each group. AD rat model was established by bilateral hippocampus injection of Aß1-40 (2 µL, 2.5 µg/µL). The next day after modeling rats in the saponin group, the benzene group, and the polysaccharide group, the saponin group, the Aricept group were intragastrically administered with saponin (at the daily dose of 9 mL/kg, 2.1 g/mL) , benzene (at the daily dose of 3.33 mL/kg, 5.7 g/mL) , polysaccharide (at the daily dose of 8.33 mL/kg, 2.28 g/mL), Aricept (at the daily dose of 1.67 mg/kg), respectively, once a day for 2 consecutive weeks from 10 am every day. Equal volume of normal saline was intragastrically administered to rats in the normal control group and the model group. Learning and memory capabilities were detected using water maze 2 weeks later. Expression levels of synaptotagmin-1 (Syt-1), interleukin-1ß (IL-1ß), glia fibrillary acidic protein (GFAP), and ß-amyloid precursor protein (ßAPP) in the cortex and hippocampus of AD rats were detected using immunohistochemistry. RESULTS: Learning and memory capabilities could be improved by three kinds extracts of QKR. There was no statistical difference in the escape latency between the polysaccharide group and the model group (P >0. 05). The escape lacency was shortened in the rest treatment groups (P < 0.05). The escape latency was obviously prolonged in three kinds extracts of QKR groups, when compared with the Aricept group (P < 0.05, P < 0.01). Compared with the model group, times for crossing platforms were significantly increased in the saponin group and the Aricept group (P < 0.05). Compared with the Aricept group, average times for crossing platforms were significantly lessened in three kinds extracts of QKR groups (P < 0.01). Compared with the sham-operation group, expression levels of Syt-1, IL-1ß, GFAP, and ßAPP in the cortex and hippocampus were increased in the model group (P < 0.01). Compared with the model group, the expression of cortical Syt-1 increased in the saponin group and the benzene group; the expression of cortical IL-1ß increased in the benzene group and the polysaccharide group; the expression of hippocampal GFAP increased in the three kinds extracts of QKR groups; expression levels of Syt-1, IL-1ß, GFAP, and ß-APP in the cortex and hippocampus decreased in the rest treatment groups (all P < 0.05, P < 0.01). Compared with the Aricept group, expression levels of Syt-1, IL-1ß, GFAP, and ßAPP in the cortex and hippocampus were significantly increased in three kinds extracts of QKR groups (P < 0.05, P < 0.01). CONCLUSION: Three kinds extracts of QKR might play roles in anti-AD possibly by decreasing expression levels of Syt-1, IL-1ß, GFAP, and ßAPP in the cortex and hippocampus.

Incidence of Orthohantavirus infection in humans follows observed changes in rodent reservoirs, Hubei Province, China (1984-2010).

OBJECTIVE: Orthohantaviruses (genus Orthohantavirus, family Hantaviridae of order Bunyavirales) are rodent-borne viruses causing 2 human diseases: hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), which are mainly prevalent in Eurasia and the Americas, respectively. We initiated this study to investigate and analyze the Orthohantaviruses infection in rodent reservoirs and humans in the Hubei Province of China from 1984 to 2010. SAMPLE: The study included 10,314 mouse and 43,753 human serum samples. PROCEDURES: In this study, we analyzed the incidence of Orthohantavirus infection in humans and observed changes in rodent reservoirs in Hubei Province. RESULTS: The results indicated that although the incidence of HFRS declined from the 1990s, the human inapparent infection did not decrease dramatically. Although elements of the disease ecology have changed over the study period, Apodemus agrarius and Rattus norvegicus remain the major species and a constituent ratio of Rattus norvegicus increased. Rodent population density fluctuated between 16.65% and 2.14%, and decreased quinquennially, showing an obvious downward trend in recent years. The average orthohantaviruses-carrying rate was 6.36%, of which the lowest rate was 2.92% from 2006 to 2010. The analysis of rodent species composition showed that Rattus norvegicus and Apodemus agrarius were the dominant species over time (68.6% [1984 to 1987] and 90.4% [2000 to 2011]), while the composition and variety of other species decreased. The density of rodents was closely related to the incidence of HFRS (r = 0.910, P = .032). CLINICAL RELEVANCE: Our long-term investigation demonstrated that the occurrence of HFRS is closely related to rodent demographic patterns. Therefore, rodent monitoring and rodent control measures for prevention against HFRS in Hubei are warranted.

Genetic characterization of a new subtype of Hantaan virus isolated from a hemorrhagic fever with renal syndrome (HFRS) epidemic area in Hubei Province, China.

To characterize hantaviruses currently circulating in the hemorrhagic fever with renal syndrome (HFRS) epidemic area of Hubei Province, rodents were captured and serum samples were collected from several HFRS patients. The partial S segment of the hantaviruses amplified from two serum samples had a high degree of sequence identity to the corresponding hantavirus strain isolated from Apodemus agrarius (designated as HV004). The complete S, M, and L segment sequences of HV004 were determined. The sequence identities between strain HV004 and other Hantaan viruses (HTNVs) were 83 %-90 % at the nucleotide level and 95 %-99 % at the amino acid level. Phylogenetic analysis showed that HV004 belonged to a new HTNV lineage. These data suggest the presence of a new HTNV subtype, which probably caused the HFRS cases in the endemic area of Hubei Province.

Effect of sacubitril valsartan on cardiac function and endothelial function in patients with chronic heart failure with reduced ejection fraction.

OBJECTIVE: The aim of the present study was to observe the effect of sacubitril valsartan on cardiac function and vascular endothelial function in patients with chronic heart failure with reduced ejection fraction (HFrEF). METHODS: A total of 80 patients with HFrEF were randomly divided into an observation group and a control group, with 40 patients in each group. Sacubitril valsartan was added to the conventional treatment in the observation group, and perindopril was added to the conventional treatment in the control group. Both groups were treated continuously for 12 weeks. The left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), flow-mediated vasodilatory function (FMD) of the brachial artery, and levels of plasma Ang II, endothelin 1 (ET-1), and calcitonin gene-related peptide (CGRP), together with the serum nitric oxide (NO) and NO synthase (NOS) were compared before and after treatment in the groups. RESULTS: Before the treatment, the levels of LVEF, LVEDD, FMD, Ang II, ET-1, CGRP, NO, and NOS in the observation group were not significantly different from those in the control group (P > 0.05). However, the levels of LVEF, FMD, CGRP, NO, and NOS in both groups were significantly higher after the treatment than those before the treatment (P < 0.05) and significantly higher in the observation group than those in the control group. The difference was statistically significant (P < 0.05). Meanwhile, the levels of LVEDD, Ang II, and ET-1 in both groups decreased significantly after the treatment (P < 0.05) and were significantly lower in the observation group than those in the control group. The difference was statistically significant (P < 0.05). CONCLUSION: Sacubitril valsartan might improve endothelial function while increasing cardiac function in HFrEF patients.

Association between interleukin-10 genetic polymorphisms and risk of primary open angle glaucoma in a Chinese Han population: a case-control study.

AIM: To investigate the association between interleukin-10 (IL-10) genetic polymorphisms and risk of POAG through a case-control study in a Han population of China. METHODS: A total of 210 patients with POAG and 420 normal subjects were recruited during the period from Dec. 2013 to Dec. 2016. The IL-10 -1082A>G (rs1800870), -819T>C (rs1800871) and -592C>A (rs1800872) polymorphisms were determined using iPlex GOLD SNP genotyping analysis (the SequenomMassARRAY® System, Sequenom, San Diego, USA). The association between IL-10 -1082A>G (rs1800870), -819T>C (rs1800871), and -592C>A (rs1800872) polymorphisms and risk of POAG was assessed by singlelogistic regression analysis. RESULTS: We observed that those carrying the CC genotype of rs1800871 was associated with an increased risk of POAG when compared with those harboring the TT genotype (OR=1.84, 95%CI=1.01-3.38). Those with AA genotype of rs1800872 had a 10.62 fold risk of POAG in comparison to the CC genotype (OR=10.62, 95%CI, 3.41-33.09). A completely linkage disequilibrium was found between IL-10 rs1800871-rs1800872 (D'=1.00, r 2=0.16). The A-C-A (OR=2.60, 95%CI, 1.48-4.58) and G-T-A (OR=2.34, 95%CI, 1.42-3.86) haplotypes were associated with an increased risk of POAG, while the A-T-C haplotype showed a decreased risk of POAG (OR=0.63, 95%CI, 0.49-0.81). CONCLUSION: Our data suggest that IL-10 rs1800871 and rs1800872 can be predictive factors for the pathogenesis of POAG in the Chinese population.

Effects of Chinese herbs on multiple ion channels in isolated ventricular myocytes.

BACKGROUND: Shensong Yangxin (SSYX) is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current (I(Na)), L-type calcium current (I(Ca, L)), transient outward potassium current (I(to)), delayed rectifier current (I(K)), and inward rectifier potassium currents (I(K1)) in isolated ventricular myocytes. METHODS: Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. RESULTS: SSYX decreased peak I(Na) by (44.84 +/- 7.65)% from 27.21 +/- 5.35 to 14.88 +/- 2.75 pA/pF (n = 5, P < 0.05). The medicine significantly inhibited the I(Ca, L). At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak I(Ca, L) was reduced by (19.22 +/- 1.10)%, (44.82 +/- 6.50)% and (50.69 +/- 5.64)%, respectively (n = 5, all P < 0.05). SSYX lifted the I - V curve of both I(Na) and I(Ca, L) without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of I(to) by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of I(K) was decreased by (30.77 +/- 1.11)% (n = 5, P < 0.05) at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of I(K) was also inhibited. Similar to the effect on I(K), the SSYX inhibited I(K1) by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. CONCLUSIONS: The experiments revealed that SSYX could block multiple ion channels such as I(Na) I(Ca, L), I(k), I(to) and I(K1), which may change the action potential duration and contribute to some of its antiarrhythmic effects.

Leaf miner-induced morphological, physiological and molecular changes in mangrove plant Avicennia marina (Forsk.) Vierh.

Avicennia marina (Forsk.) Vierh is a widespread mangrove species along the southeast coasts of China. Recently, the outbreak of herbivorous insect, Phyllocnistis citrella Stainton, a leaf miner, have impacted on the growth of A. marina. Little is reported about the responses of A. marina to leaf miner infection at the biochemical, physiological and molecular levels. Here, we reported the responses of A. marina to leaf miner infection from the aspects of leaf structure, photosynthesis, and antioxidant system and miner responsive genes expression. A. marina leaves attacked by the leaf miner exhibited significant decreases in chlorophyll, carbon and nitrogen contents, as well as a decreased photosynthetic rate. Scanning and transmission electron microscopic observations revealed that the leaf miner only invaded the upper epidermis and destroyed the epidermal cell, which lead to the exposure of salt glands. In addition, the chloroplasts of mined leaves (ML) were swollen and the thylakoids degraded. The maximal net photosynthetic rate, stomatal conductance (Gs), carboxylation efficiency (CE), dark respiration (Rd), light respiration (Rp) and quantum yields (AQE) significantly decreased in the ML, whereas the light saturation point (Lsp), light compensation point (Lcp), water loss and CO2 compensation point (Г) increased in the ML. Moreover, chlorophyll fluorescence features also had been changed by leaf miner attacks. Interestingly, higher generation rate of O2ˉ· and lower antioxidant enzyme expression in the mined portion (MP) were found; on the contrary, higher H2O2 level and higher antioxidant enzyme expression in the non-mined portion (NMP) were revealed, implying that the NMP may be able to sense that the leaf miner attacks had happened in the MP of the A. marina leaf via H2O2 signaling. Besides, the protein expression of glutathione S-transferase (GST) and the glutathione (GSH) content were increased in the ML. In addition, insect resistance-related gene expression such as chitinase 3, RAR1, topless and PIF3 had significantly increased in the ML. Taken together, our data suggest that leaf miners could significantly affect leaf structure, photosynthesis, the antioxidant system and miner responsive gene expression in A. marina leaves.

Effects of calcitriol on random skin flap survival in rats.

Calcitriol, a metabolite of vitamin D, is often used in osteoporosis clinics. However, the material has other bioactivities; for example, it accelerates angiogenesis, has anti-inflammatory properties, and inhibits oxidative stress. We investigated the effects of calcitriol in a random skin flap rat model. "McFarlane flap" models were established in 84 male Sprague Dawley rats, divided into two groups. One group received intraperitoneal injections of calcitriol (2 µg/kg/day) whereas control rats received intraperitoneal injections of saline. The percentage flap survival area and tissue water content were measured 7 days later, which showed that calcitriol improved flap survival area and reduced tissue edema. It also increased the mean vessel density and upregulated levels of VEGF mRNA/protein, both of which promote flap angiogenesis. Moreover, it decreased leukocyte and macrophage infiltration, reduced the inflammatory proteins IL1ß and IL6, increased SOD activity, decreased MDA content, and upregulated the level of autophagy. Overall, our results suggest that calcitriol promotes skin flap survival by accelerating angiogenesis, having anti-inflammatory effects, reducing oxidative stress, and promoting autophagy.

The epidemic characteristics and changing trend of hemorrhagic fever with renal syndrome in Hubei Province, China.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is caused by different hantaviruses within the Bunyaviridae family. HFRS is a fulminant, infectious disease that occurs worldwide and is endemic in all 31 provinces of China. Since the first HFRS case in Hubei Province was reported in 1957, the disease has spread across the province and Hubei has become one of the seriously affected areas in China with the greatest number of reported HFRS cases in the 1980's. However, the epidemic characteristics of HFRS in Hubei are still not entirely clear and long-term, systematic investigations of this epidemic area have been very limited. METHODS: The spatiotemporal distribution of HFRS was investigated using data spanning the years 1980 to 2009. The annual HFRS incidence, fatality rate and seasonal incidence between 1980 and 2009 were calculated and plotted. GIS-based spatial analyses were conducted to detect the spatial distribution and seasonal pattern of HFRS. A spatial statistical analysis, using Kulldorff's spatial scan statistic, was performed to identify clustering of HFRS. RESULTS: A total of 104,467 HFRS cases were reported in Hubei Province between 1980 and 2009. Incidence of and mortality due to HFRS declined after the outbreak in 1980s and HFRS cases have been sporadic in recent years. The locations and scale of disease clusters have changed during the three decades. The seasonal epidemic pattern of HFRS was characterized by the shift from the unimodal type (autumn/winter peak) to the bimodal type. CONCLUSIONS: Socioeconomic development has great influence on the transmission of hantaviruses to humans and new epidemic characteristics have emerged in Hubei Province. It is necessary to reinforce preventative measures against HFRS according to the newly-presented seasonal variation and to intensify these efforts especially in the urban areas of Hubei Province.

[Studies on spatial heterogeneity of soil respiration in a subalpine meadow].

We measured soil respiration (R) and the environmental factors influencing Rs including soil temperature ( T, ) , soil water content (SWC) and soil organic carbon (SOC) in a subalpine meadow in Yundin mountain of Shanxi province, and performed an analysis of the heterogeneity of Rs, T10 and SWC and SOC as well as their relationships using both traditional statistics and geostatistics methods. The results from traditional statistics showed that the measured data of R and the environmental factors exhibited a normal distribution with variation coefficients ranging between 12% and 24%. The variation of all the measured factors was in the middle range. The fact that the correlation coefficient between Rs, and SOC (r =0. 61) was larger than that between Rs, and T15(r =0. 27) and SWC (r = 0. 26) indicates that the heterogeneity of Rs was controlled mainly by SOC. The results from geostatistics analyses showed that linear model could reflect the spatial characteristics of Rs and the environmental factors. The C0/(C0 + C) values for Rs, T10, SWC and SOC were 41% , 3% , 77% , and 57% , respectively, indicating that the spatial heterogeneities of both RB and T10 were resulted mainly from structural factor, but the spatial heterogeneities of SWC and SOC were controlled mainly by random factor. The range of semi-variogram function was 53. 2 m for Rs, T, and SWC, and 52. 1 m for SOC. The fractal dimension value of Rs, T10, SWC, and SOC was 1. 85, 1. 60, 1. 96, and 1. 95, respectively, indicating that SWC had the weakest spatial dependence on scale and the most complicated spatial distribution pattern, while T10 had the simplest spatial distribution pattern. The spatial distribution of Rs showed a similar distribution character to both SWC and SOC, but had its own regularity. With the decrease of the confidence level and the estimated accuracy, the required sampling number of the Rs and the environmental factors measurements declined substantially.

[Effect of vegetation types on soil respiration characteristics on a smaller scale].

Soil respiration was measured from April 2005 to December 2007 using a LICOR-6400-09 chamber connecting a LiCor-6400 portable photosynthesis system at 3 sites with same elevation and soil texture but different vegetation types. The results indicated that seasonal trend of soil respiration showed a distinct temporal change with the higher values in summer and autumn months and the lower values in winter and spring. Annual means (March to December) of soil respiration for 3 the sampling sites were(3.58 +/- 2.50), (3.82 +/- 2.75) and (4.42 +/- 3.38) micromol x (m2 x s)(-1) (p > 0.05), respectively. Released annual amount (March to December) of CO2 efflux from 3 sites was from 854.9 to 1 297.2 g x (m2 x a)(-1) and the amount was no difference between sites and among years. The fitted exponential equations of soil respiration and soil temperature for 3 sites were all significant with the R2 from 0.61 to 0.81, and the Q10 and R10 calculated from fitted parameters of the equations ranged from 2.60 to 4.50, and from 1.70 to 3.02 micromol x (m2 x s)(-1). The relationships between soil respiration and soil water content were not significant for all 3 sites with a maximum R2 of the regression equations only 0.12 (p > 0.05). However, when the soil temperature was above 10 degrees C, the relationships between soil respiration and soil water content was significant (p < 0.05). Four combined regression equations including soil temperature and soil water content could be used to model relationships between soil respiration and both soil temperature and soil water content together, with the R2 most above 0.7, and maximum of 0.91.

Hydrolysis of acetylthiocholine iodide and reactivation of phoxim-inhibited acetylcholinesterase by pralidoxime chloride, obidoxime chloride and trimedoxime.

The hydrolysis of acetylthiocholine iodide (ATCh) by pralidoxime chloride (2-PAM Cl), trimedoxime (TMB(4)) and obidoxime chlpride (LUH(6)) was studied at pH 5.8-8.0 and incubation temperature from 5 to 40 degrees C in vitro. Significant ATCh hydrolysis by 2-PAM Cl, TMB(4) and LUH(6) was found, with the exceptions of those at pH 7.0, 6.2 and 5.8 at 5 degrees C and those at pH 6.2 and 5.8 at 15 degrees C. The hydrolysis by TMB(4) and LUH(6) was significantly stronger than that by 2-PAM Cl. The hydrolysis increased with increasing pH, incubation temperature and three oxime or ATCh concentration. Significant hydrolysis of ATCh by the three oximes could be found when the terminal concentration of oxime was higher than 0.01 mM at pH 7.0 and 7.4 at 30 and 37 degrees C. However, no hydrolysis of natural substrate (acetylcholine iodide) by the three oximes was found when very high terminal concentrations of oximes were used. In addition, the three oximes displayed an extraordinary efficiency in the reactivation of phoxim-inhibited acetylcholinesterase (AChE) from fish (Carassius auratus) or rabbit (Oryctolagus cuniculus domestic) brain in vitro. Parallel to the level of ATCh hydrolysis by the oximes, TMB(4) and LUH(6) displayed significantly higher reactivation efficiency than 2-PAM Cl to phoxim-inhibited AChE. And, the extent of reactivation by 2-PAM Cl was also lower than the other two. Plausible antidotal actions of the oximes against organophosphate poisoning AChE and erroneously high estimation of AChE activity by the Ellman method were discussed.

[Algaecidal effect of a nanomaterial sheet].

A nanomaterial algaecidal sheet was prepared for algaecidal treatment. The results of algaecidal activity of the nanomaterial algaecidal sheet in lab and field experiments were investigated. It was showed that under the ratio of the area of nanomaterial algaecidal sheet to the volume of algal cell suspension at 0.08 cm2 x mL(-1) and light intensity at 3000 1x, the cell density of algal cell suspension of Microcystis aeruginosa, Anabaena 7120, Euglena gracilis, and Chlamydomonas reinhardtii decreased by 77%, 69.1%, 89.1% and 56.9% respectively after 24 h treatment, and Chla concentration of algal cell suspension of Navicula incerta decreased by 18.7%. Chla concentration of a site with algal bloom in Wuli Lake decreased by 76% after 1 day treatment in the field experiment. Acute fish toxicity test (5 days) of the nanomaterial algaecidal sheet showed no significant toxicity.