[Risk factors for embolism in children with refractory Mycoplasmapneumoniae pneumonia and construction of a nomogram model for prediction of embolism]. / éš¾æ²»æ€§è‚ºç‚Žæ”¯åŽŸä½“è‚ºç‚Žæ‚£å„¿åˆå¹¶æ “å¡žçš„å±é™©å› ç´ åˆ†æžåŠåˆ—çº¿å›¾é¢„æµ‹æ¨¡åž‹çš„æž„å»º.

OBJECTIVES: To study the risk factors for embolism in children with refractory Mycoplasma pneumoniae pneumonia (RMPP) and to construct a nomogram model for prediction of embolism. METHODS: This retrospective study included 175 children diagnosed with RMPP at Children's Hospital Affiliated toZhengzhou University from January 2019 to October 2023. They were divided into two groups based on the presence of embolism: the embolism group (n=62) and the non-embolism group (n=113). Multivariate logistic regression analysis was used to screen for risk factors of embolism in children with RMPP, and the R software was applied to construct the nomogram model for prediction of embolism. RESULTS: Multivariate logistic regression analysis indicated that higher levels of D-dimer, interleukin-6 (IL-6) and neutrophil to lymphocyte ratio (NLR), lung necrosis, and pleural effusion were risk factors for embolism in children with RMPP (P<0.05). The area under the curve of the nomogram model for prediction of embolism constructed based on the aforementioned risk factors was 0.912 (95%CI: 0.871-0.952, P<0.05). The Hosmer-Lemeshow goodness-of-fit test showed that the model had a good fit with the actual situation (P<0.05). Calibration and decision curve analysis indicated that the model had high predictive efficacy and clinical applicability. CONCLUSIONS: Higher levels of D-dimer, IL-6 and NLR, lung necrosis, and pleural effusion are risk factors for embolism in children with RMPP. The nomogram model based on these risk factors has high clinical value for predicting embolism in children with RMPP.

[Voluntary wheel running exercise regulates microglia polarization in hippocampus through STAT3 signal pathway to inhibit depression-like behavior induced by chronic stress in rats].

This paper was aimed to investigate the effect of voluntary wheel running exercise on depression-like behavior induced by chronic water immersion restraint stress (CWIRS) and the underlying mechanism. Sprague-Dawley (SD) rats received CWIRS to induce depression-like behavior and 4-week voluntary wheel running exercise. Meanwhile, the rats were treated with lipopolysaccharide (LPS) or STAT3 over-expression vector (pcDNA-STAT3) by intracerebroventricular injection. Behavioral tests were used to detect depression-like behavior. ELISA assay was used to detect levels of various inflammatory factors in the rat hippocampus. Western blot was used to detect protein expression levels of ionized calcium binding adaptor molecule 1 (Iba1), inducible nitric oxide synthase (iNOS), arginase 1 (Arg1), phosphorylated STAT3 (p-STAT3) and total STAT3 (t-STAT3). The results showed that, compared with stress group, stress + exercise group exhibited improved depression-like behavior, decreased interleukin-1ß (IL-1ß) and IL-6 levels, increased IL-4 and IL-10 levels, down-regulated Iba-1 and iNOS protein expression levels, up-regulated Arg1 protein expression level, and decreased p-STAT3/t-STAT3 ratio in hippocampal tissue. LPS reversed the improving effect of voluntary wheel running exercise on depression-like behavior in rats, and the over-expression of STAT3 reversed the promoting effects of voluntary wheel running on M2 polarization of microglial cells in rat hippocampus and depression-like behavior. These results suggest that voluntary wheel running ameliorates the depression-like behavior induced by CWIRS in rats, and the mechanism may be related to regulating hippocampal microglia polarization via STAT3 signaling pathway.

[A comparative analysis of anti-N-methyl-D-aspartate receptor encephalitis with or without abnormal findings on cranial magnetic resonance imaging].

OBJECTIVE: To investigate the clinical features of children with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis with normal or abnormal cranial magnetic resonance imaging (MRI) findings via a comparative analysis. METHODS: A retrospective analysis was performed for the clinical data of 33 children with anti-NMDAR encephalitis. The clinical features and prognosis were compared between the children with normal and abnormal cranial MRI findings. RESULTS: In the 33 children with anti-NMDAR encephalitis, the most common initial symptoms were seizures (61%) and involuntary movement (61%), followed by language disorder (54%), mental and behavioral abnormalities (52%), and disturbance of consciousness (30%). All children had positive anti-NMDAR antibody in the cerebrospinal fluid, and 29 children (88%) had positive serum antibody. Of all the children, 15 (46%) had increased leukocytes in the cerebrospinal fluid, 3 (9%) had an increase in protein, and 29 (88%) had positive oligoclonal band; 26 children (79%) had electroencephalographic abnormalities (epileptic wave, slow wave, or a combination of these two types of waves). One child experienced respiratory failure. One child was found to have germinoma in the sellar region during follow-up. Of all the 33 children, 13 (39%) had abnormal cranial MRI findings, with hypointensity or isointensity on T1W1 and hyperintensity on T2WI and T2-FLAIR; 2 children had dural enhancement. As for the location of lesion, 5 children (38%) had lesions in the temporal lobe, 3 (23%) in the frontal lobe, 3 (23%) in the basal ganglia, 2 (15%) in the parietal lobe, 2 (15%) in the occipital lobe, 2 (15%) in the brainstem, 1 (8%) in the thalamus, and 1 (8%) in the cerebellum. Among the 13 children with abnormal cranial MRI findings, 5 (38%) had lesions mainly in the grey matter and 8 (62%) had lesions mainly in the white matter. Compared with the children with normal cranial MRI findings, the children with abnormal cranial MRI findings had significantly higher proportion of children with prodromal infection, incidence rate of disturbance of consciousness, probability of recurrence, Glasgow score, incidence rate of increased leukocytes in the cerebrospinal fluid, and application rate of second-line treatment (P<0.05). CONCLUSIONS: Children with anti-NMDAR encephalitis and abnormal cranial MRI findings have certain clinical features, which may provide guidance for the evaluation of disease conditions and the selection of diagnostic and treatment measures.

Photosynthetic carbon allocation in native and invasive salt marshes undergoing hydrological change.

Biogeochemical processes mediated by plants and soil in coastal marshes are vulnerable to environmental changes and biological invasion. In particular, tidal inundation and salinity stress will intensify under future rising sea level scenarios. In this study, the interactive effects of flooding regimes (non-waterlogging vs. waterlogging) and salinity (0, 5, 15, and 30 parts per thousand (ppt)) on photosynthetic carbon allocation in plant, rhizodeposition, and microbial communities in native (Phragmites australis) and invasive (Spartina alterniflora) marshes were investigated using mesocosm experiments and 13CO2 pulse-labeling techniques. The results showed that waterlogging and elevated salinity treatments decreased specific root allocation (SRA) of 13C, rhizodeposition allocation (RA) 13C, soil 13C content, grouped microbial PLFAs, and the fungal 13C proportion relative to total PLFAs-13C. The lowest SRA, RA, and fungal 13C proportion occurred under the combined waterlogging and high (30 ppt) salinity treatments. Relative to S. alterniflora, P. australis displayed greater sensitivity to hydrological changes, with a greater reduction in rhizodeposition, soil 13C content, and fungal PLFAs. S. alterniflora showed an earlier peak SRA but a lower root/shoot 13C ratio than P. australis. This suggests that S. alterniflora may transfer more photosynthetic carbon to the shoot and rhizosphere to facilitate invasion under stress. Waterlogging and high salinity treatments shifted C allocation towards bacteria over fungi for both plant species, with a higher allocation shift in S. alterniflora soil, revealing the species-specific microbial response to hydrological stresses. Potential shifts towards less efficient bacterial pathways might result in accelerated carbon loss. Over the study period, salinity was the primary driver for both species, explaining 33.2-50.8 % of 13C allocation in the plant-soil-microbe system. We propose that future carbon dynamics in coastal salt marshes under sea-level rise conditions depend on species-specific adaptive strategies and carbon allocation patterns of native and invasive plant-soil systems.

[Effects of receptor interacting protein 140 on the biological activity of glia cells].

OBJECTIVE: To explore the effects of receptor interacting protein (RIP) 140 gene overexpression upon the in vitro proliferation, apoptosis, invasion and migration of microglioma cells. METHODS: The BV-2 RIP140 overexpression model (BV-2-1) was constructed by Lipofection and G418 selection, then validated by real-time PCR and Western blotting. The proliferation, apoptosis, invasion and migration potencies were compared between BV-2-1 and its parents by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay, flow cytometry and Transwell chamber. RESULTS: The BV-2-1 model was successfully constructed. Compared to those of the BV-2 group, the RIP140 mRNA and protein expression levels of BV-2-1 were markedly higher than those of the BV-2 group (t = 49.794, P < 0.01). MTT assay showed that the absorbance values in the BV-2 group were 1.157 ± 0.013, 1.679 ± 0.005 and 2.609 ± 0.008 at 24, 48, and 72 hours respectively. And those were 0.929 ± 0.013, 1.188 ± 0.008 and 1.528 ± 0.012 in the BV-2-1 group respectively. The proliferation at the time points of 48 and 72 hours of the BV-2-1 group were significantly lower than that of the BV-2 group (t = 6.058 and 9.245, both P < 0.01). Annexin-V staining showed that there were significant differences in the apoptosis rates between the BV-2 and BV-2-1 cells [(5.35 ± 0.23)% vs (3.46 ± 0.45)%, t = 6.619, P = 0.003)]. Transwell assay showed that the invaded cell number of the BV-2-1 group was 166 ± 43. And it was obviously higher than that of the BV-2 group (93 ± 32, t = 3.403, P = 0.007). Transwell assay also showed that the migrated cell number of BV-2 cells was 101 ± 25. And the migration potency of the BV-2-1 group (202 ± 50) was significantly stronger than that of the BV-2 group (t = 4.104, P = 0.002). CONCLUSION: RIP140 effectively inhibits the proliferation and facilitates the apoptosis of microglioma cells. And it may effectively facilitate the in vitro invasion and migration of microglioma cells.

Reclamation-induced tidal restriction increases dissolved carbon and greenhouse gases diffusive fluxes in salt marsh creeks.

Intertidal creeks play an important role in transporting nutrients between coastal ecosystems and ocean. Reclamation is a predominant anthropogenic disturbance in coastal regions; however, the influence of reclamation on carbon and nitrogen species and greenhouse gas (GHG) fluxes in creek remains unclear. In a subtropical salt marsh of eastern China, the seasonal patterns of dissolved carbon (DOC, DIC, CO2, and CH4) and inorganic nitrogen (NH4+-N, NO2--N, and NO3--N and N2O) species, and the diffusive fluxes of CO2, CH4, and N2O, were compared between the natural tidal creeks and the reclaimed creeks. Due to notably changed hydrological and biological conditions in the reclaimed creeks, concentrations of all dissolved carbon species, NH4+-N and NO2--N increased significantly by 60.2-288.2%, while NO3--N and N2O decreased slightly, compared to the natural tidal creeks. DIC and NO3--N were the primary components of the total dissolved carbon and inorganic nitrogen in both creek types; however, their proportions decreased as a result of elevated DOC, CO2, CH4, NH4+-N, and NO2--N following reclamation. Significantly higher global warming potential (0.58 ± 0.15 g CO2-eq m-2 d-1) was found in the reclaimed creeks, making them hotspot of greenhouse effects, compared to the natural tidal creeks. Our results indicated that changes in flow velocity, salinity, Chlorophyll a, and pH were the main factors controlling the dissolved carbon and nitrogen and consequent GHG emissions, due to reclamation. This study is helpful in understanding of carbon and nitrogen sink-source shifts resulting from land use changes in coastal wetlands.

Sea-level rise will reduce net CO2 uptake in subtropical coastal marshes.

Coastal marshes have a significant capacity to sequester carbon; however, sea-level rise (SLR) is expected to result in prolonged flooding and saltwater intrusion in coastal regions. To explore the effects of SLR projections on net CO2 uptake in coastal marshes, we conducted a "double-check" investigation, including the eddy covariance (EC) measurements of the CO2 fluxes in subtropical coastal marshes along inundation and salinity gradients, in combination with a mesocosm experiment for analyzing CO2 flux components under waterlogging and increased salinity conditions. During the same measurement periods, the net ecosystem CO2 exchange (NEEEC based on the EC dataset) in an oligohaline marsh was higher than that in a low-elevation mesohaline marsh, whereas the NEEEC was lower than that in a high-elevation freshwater marsh. The declines in NEEEC between the marshes could be attributed to a greater decrease in gross primary production relative to ecosystem respiration. Waterlogging slightly increased the NEEms (NEE based on the mesocosms) because of inhibited soil respiration and slight changes in plant photosynthesis and shoot respiration. However, the NEEms measured during the drainage period decreased significantly due to the stimulated soil respiration. The NEEms decreased with increasing salinity (except under mild salinity), and waterlogging exacerbated the adverse impacts of salinity. The amplificatory effect of decreases in both leaf photosynthesis and growth under hydrological stresses contributed more to reduce the NEEms than to respiratory effluxes. Both waterlogging and increased salinity reduced the root biomass, soil microbial biomass, and activities of assayed soil enzymes (except for cellulase under waterlogging conditions), leading to limited soil respiration. The declines in plant growth, photosynthesis, and soil respiration could also be attributed to the decrease in soil nutrients under waterlogging and increased salinity conditions. We propose that the coupling of SLR-driven hydrological effects lowers the capacity of CO2 uptake in subtropical coastal marshes.

[Manual Acupuncture Stimulation of Paired Acupoints Can Relieve Sleep Disorder Possibly by Upregulating Pineal Melatonin Protein and Its Receptor mRNA Levels in the Suprachiasmatic Nucleus in Insomnia Rats].

OBJECTIVE: To observe the effect of manual acupuncture stimulation of paired "Baihui" (GV 20)+ "Shenmen" (HT 7), GV 20+ "Sanyinjiao" (SP 6), and GV 20+ non-acupoint on expression of melatonine (MT) and suprachiasmatic melatonin receptor 1 (MT1) and melatonin receptor 2 (MT2) mRNAs in insomnia rats, so as to explore their action difference and the underlying mechanism in improving insomnia. METHODS: Male SD rats were randomly divided into normal control (n=12), mo-del (n=8), GV 20+HT 7(n=12), GV 20+SP 6(n=11), and GV 20+ non-acupoint (n=10) groups. The insomnia model was established by intraperitoneal injection of Para-chlorophenylalanine suspension (50 mg/mL, 50 mg/100 g), once daily for 2 days. The abovementioned acupoints GV 20, bilateral HT 7, SP 6 and non-acupoints (the midpoint between the elbow-tip and armpit on the medial side of the upper-arm) were punctured with filiform needles and manipulated by rotating the needle for about 1 min which was repeated once again every 10 min during 30 minutes' needle-retaining. The treatment was conducted once daily for 7 days. The expression levels of MT immunoactivity in the conarium tissue, and MT1 and MT2 mRNAs of the suprachiasmatic nucleus (SCN) region were detected using immunohistochemistry and fluorescence quantitative real time-PCR, respectively. RESULTS: After modeling, the expression levels of pineal MT (an increase of gray value means a decrease of immunoactivity), SCN MT1 and MT2 mRNAs were notably down-regulated in the model group relevant to the normal control group (P<0.05, P<0.01). Following the treatment, the down-regulated expression levels of MT protein, and MT1 and MT2 mRNAs were obviously reversed in the GV 20 + HT 7, GV 20 + SP 6 groups relevant to the model group (P<0.05, P<0.01). The therapeutic effect of GV 20+ HT 7 was superior to that of GV 20+ non-acupoint in up-regulating the expression of MT1 mRNA (P<0.01), and markedly superior to that of GV 20+ SP 6 and GV 20+ non-acupoint in increasing the sleep duration and in up-regulating the expression of MT2 mRNA (P<0.01). No significant differences were found among the 3 treatment groups in up-regulating the expression of MT (P>0.05). CONCLUSION: Manual acupuncture stimulation of GV 20+ HT 7 and GV 20+ SP 6 can improve the sleep disorder in insomnia rats, which may be related to its effects in increasing the levels of pineal MT protein, and MT1 and MT2 mRNAs in hypothalamic SCN.

Ecophysiological response of native and exotic salt marsh vegetation to waterlogging and salinity: Implications for the effects of sea-level rise.

The ecophysiological characteristics of native Phragmites australis and exotic Spartina alterniflora grown under waterlogging and salinity were investigated to explore their adaptation potential to sea level rise. The seasonal course of phenotypic traits, photosynthetic activity and chlorophyll fluorescence parameters of P. australis did not change remarkably under shallow flooding, whereas these variables were sensitive to increasing salinity. Waterlogging exacerbated the negative effects of salinity on shoot growth and photosynthetic activity of P. australis, and the combined stresses led to an absence of tassel and reproductive organs. By contrast, S. alterniflora performed well under both stresses and showed an obvious adaptation of salt secretion with increasing salinity. Light salinity was the optimal condition for S. alterniflora, and the tassel growth, chlorophyll content and fluorescence characters under moderate stresses did not differ notably. The Na+ and Cl- concentrations in leaves of both species increased, and the K+ content decreased in response to salinity. Under moderate and high saline levels, the ion concentrations in S. alterniflora were maintained at relatively consistent levels with increased salt secretion. We expect the degradation of P. australis and further colonization of S. alterniflora under prolonged flooding and saltwater intrusion from sea level rise on the coastline of China.

[Effects of Herbal-cake-separated Moxibustion on Blood Lipid Protein Levels and Expression of Toll-like Receptor and Nuclear Factor Genes in Atherosclerotic Plaques in Hyperglycemia Rabbits].

OBJECTIVE: To observe the effect of herbal cake-separated moxibustion on blood lipid-apoprotein levels and the expression of Toll-like receptor 2 (TLR 2), TLR 4 and nuclear factor kappa B(NF-κB) mRNAs in atherosclerotic (AS) vulnerable plaques of hyperglycemia rabbits, so as to explore its mechanism underlying improvement of atherosclerosis. METHODS: Sixty New Zealand rabbits were randomly divided into 5 groups: control, model, direct moxibustion, herbal-cake-separated moxibustion and medication groups(n＝12 rabbits in each group). The AS vulnerable plaque model was established by high-fat forage feeding plus balloon-induced abdominal aorta injury and gene transfection of Ad 5-p 53 recombinant vector. Direct moxibustion or herbal-cake-separated moxibustion was applied to "Juque" (CV 14) and bilateral "Tianshu" (ST 25), "Fenglong" (ST 40), or bilateral "Xinshu" (BL 15), "Pishu" (BL 20) and "Ganshu" (BL 18) for 15－20 min every time. The medication group was treated by feeding Atorvastatin. All the treatments were conducted once daily for 8 weeks. Plasma total cholesterol(TC) and triglyceri-de(TG) contents were detected by enzyme method, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) contents detected by colorimetric determination, and plasma apolipoprotein A(Apo-A) and apolipoprotein B(Apo-B) levels determined by electrophoretic method. The pathological changes of vulnerable plaque and the aortic intima and media thickness were observed under light microscope after H．E. staining. The expression levels of TLR 2, TLR 4 and NF-κB mRNAs in AS plaques were determined by quantitative real-time PCR. RESULTS: After modeling, the levels of plasma TC, TG, LDL and Apo-B in the model group were remarkably increased (P<0.01), and Apo-A and HDL/LDL were significantly decreased in comparison with the control group (P<0.01). Additionally, the aortic intima and media thickness and the expression levels of TLR 2, TLR 4 and NF-κB mRNAs in AS plaques were significantly increased (P<0.01). After the treatment, the elevated levels of plasma TC, TG, LDL and Apo-B, the aortic intima thickness and media thickness, and the expression levels of TLR 2, TLR 4 and NF-κB mRNAs in the 3 treatment groups were significantly down-regulated in comparison with the model group (P<0.05, P<0.01), while the decreased levels of Apo-A and HDL/LDL were considerably increased (P<0.01). Comparison among the 3 treatment groups showed that the therapeutic effects of the herbal-cake-separated moxibustion and medication were significantly superior to those of the direct moxibustion in down-regulating the levels of TC, TG, LDL, Apo-B, TLR 2 mRNA, TLR 4 mRNA and NF-κB mRNA, and reducing the thickness of the aortic intima and media, as well as in up-regulating the levels of Apo-A and HDL/LDL (P<0.05, P<0.01). No significant differences were found between the herbal-cake-separated moxibustion and medication groups in the above-mentioned indexes (P>0.05). CONCLUSION: Herbal-cake-separated moxibustion has a positive role in stabilizing AS vulnerable plaque in hyperglycemia rabbits, which may be associated with its effects in regulating blood lipid-apolipoprotein levels and inhibiting the expression of TLR 2, TLR 4 and NF-κB mRNAs in vulnerable plaques.

[Effect of Acupuncture Stimulation of Different Acupoint Combinations on Sleep and Expression of Circadian Clock and Bmal 1 Genes in Hypothalamus of Insomnia Rats].

OBJECTIVE: To observe the effect of manual acupuncture stimulation (MAS) of "Baihui"(GV 20)-"Shenmen"(HT 7)or GV 20-"Sanyinjiao"(SP 6) on sleep and expression of circadian rhythm genes (Clock and Bmal 1) in the hypothalamus in insomnia rats, so as to select a better acupoint group for insomnia. METHODS: A total of 53 SD rats were randomly divided into normal control (n=12),insomnia model (n=8), GV 20-HT 7(n=12), GV 20-SP 6(n=11),and GV 20-non-acupoint (n=10) groups. The insomnia model was established by intraperitoneal injection of p-chlorophenylalanine (PCPA,500 mg/kg,100 mg/mL) once daily for 2 days. The MAS (uniform reinforcing-reducing needling) was applied to GV 20-HT 7, GV 20-SP 6 or GV 20-non-acupoint for 30 min,once daily for 7 days. The sleep onset latency and sleep duration were gauged after intraperitoneal injection of pentobarbital sodium (35 mg/kg). The expression levels of Clock mRNA and Bmal 1 mRNA in the hypothalamic tissues containing ventrolateral preoptic area (VLPO) and suprachiasmatic nucleus (SCN) region were detected by fluorescence quantitative real-time PCR. RESULTS: Following administration of pentobarbital sodium,the sleep latency was significantly prolonged and the sleep duration was considerably shortened in rats of the model group(P<0.05). After the treatment, the increased sleep latencies in the GV 20-HT 7, GV 20-SP 6 and GV 20-non-acupoints were all significantly down-regulated (P<0.05), and the decreased sleep duration was significantly increased only in the GV 20-HT 7 group relevant to the model group (P<0.05), but not in the GV 20-SP 6 and GV 20-non-acupoint groups (P<0.05). There were no significant differences in the sleep latency among the 3 treatment groups (P<0.05). The sleep duration was obviously prolonged in the GV 20-HT 7 group than in the GV 20-SP 6 and GV 20-non-acupoint groups (P<0.05). After modeling, the expression levels of Clock mRNA and Bmal 1 mRNA in hypothalamic VLPO and SCN regions were significantly down-regulated relevant to the normal control group (P<0.01). Following the treatment, the expression levels of Clock mRNA in the VLPO and SCN regions of the GV 20-SP 6 and GV 20-HT 7 groups, and those of Bmal 1 mRNA in the VLPO and SCN regions of the 3 treatment groups were considerably increased relevant to the model group (P<0.05, P<0.01). The effects of GV 20-HT 7 were significantly superior to those of GV 20-SP 6 and GV 20-non-acupoint (and also the action of GV 20-SP 6 was evidently superior to that of GV 20-non-acupoint) in up-regulating the expression of Clock mRNA and Bmal 1 mRNA in both VLPO and SCN regions (P<0.05, P<0.01). CONCLUSIONS: Manual acupuncture stimulation of GV 20-HT 7 can improve the sleep latency and duration in insomnia rats,which may be associated with its effects in up-regulating the expression levels of circadian Clock mRNA and Bmal 1 mRNA in hypothalamic VLPO and SCN regions, and the efficacy of GV 20-HT 7 is obviously better than that of GV 20-SP 6 and GV 20-non-acupoint.

[Correlation Among Soil Organic Carbon, Soil Inorganic Carbon and the Environmental Factors in a Typical Oasis in the Southern Edge of the Tarim Basin].

We analyzed the differentiation among the environmental factors and soil organic/inorganic carbon contents of irrigated desert soil, brown desert soil, saline soil and aeolian sandy soil by classical statistics methods, and studied the correlation between soil carbon contents and the environmental factor by redundancy analysis (RDA) in a typical oasis of Yutian in the southern edge of the Tarim Basin. The results showed that the average contents of soil organic carbon and soil inorganic carbon were 2.51 g · kg⁻¹ and 25.63 g · kg⁻¹ respectively. The soil organic carbon content of the irrigated desert soil was significantly higher than those of brown desert soil, saline soil and aeolian sandy soil, while the inorganic carbon content of aeolian sandy soil was significantly higher than those of other soil types. The soil moisture and nutrient content were the highest in the irrigated desert soil and the lowest in the aeolian sandy sail. All soil types had high degree of salinization except the irrigated desert soil. The RDA results showed that the impacts of environmental factors on soil carbon contents ranked in order of importance were total nitrogen > available phosphorus > soil moisture > ground water depth > available potassium > pH > total salt. The soil carbon contents correlated extremely significantly with total nitrogen, available phosphorus, soil moisture and ground water depth (P < 0.01), and it correlated significantly with available potassium and pH (P < 0.05). There was no significant correlation between soil carbon contents and other environmental factors (P > 0.05).

Changes in spatial patterns of Caragana stenophylla along a climatic drought gradient on the Inner Mongolian Plateau.

Few studies have investigated the influence of water availability on plant population spatial patterns. We studied changes in the spatial patterns of Caragana stenophylla along a climatic drought gradient within the Inner Mongolian Plateau, China. We examined spatial patterns, seed density, "nurse effects" of shrubs on seedlings, transpiration rates and water use efficiency (WUE) of C. stenophylla across semi-arid, arid, and intensively arid zones. Our results showed that patches of C. stenophylla populations shifted from a random to a clumped spatial pattern towards drier environments. Seed density and seedling survival rate of C. stenophylla decreased from the semi-arid zone to the intensively arid zone. Across the three zones, there were more C. stenophylla seeds and seedlings underneath shrub canopies than outside shrub canopies; and in the intensively arid zone, there were almost no seeds or seedlings outside shrub canopies. Transpiration rates of outer-canopy leaves and WUE of both outer-canopy and inner-canopy leaves increased from the semi-arid zone to the intensively arid zone. In the intensively arid zone, transpiration rates and WUE of inner-canopy leaves were significantly lower and higher, respectively, than those of outer-canopy leaves. We conclude that, as drought stress increased, seed density decreased, seed proportions inside shrubs increased, and "nurse effects" of shrubs on seedlings became more important. These factors, combined with water-saving characteristics associated with clumped spatial patterns, are likely driving the changes in C. stenophylla spatial patterns.

Inhibitory effect of propylene glycol mannate sulfate on growth of rabbit lens epithelial cells in vitro.

AIM: To investigate the inhibitory effect of rabbit lens epithelial cell (RLEC) survival and growth by propylene glycol mannate sulfate (PGMS) on the rabbit capsular bag in vitro. METHODS: Capsular bags were prepared from rabbit eyes after extracapsular cataract extraction (ECCE) and incubated in 0.2, 0.4, 0.8g/L PGMS in 2, 5, 10 minutes incubation periods. After treatment, the capsular bags were cultured for 7 days in Dulbecco minimum essential medium (DMEM) supplemented with 50mL/L fetal calf serum (FCS). The specimens were examined with light microscopy and transmission electron microscopy (TEM). Capsular bags without receiving PGMS only served as controls. RESULTS: PGMS inhibited the proliferation of RLEC in the manner of concentration and time dependent. At the threshold protocol of incubation in PGMS at 0.8g/L for 5 or 10 minutes, proliferative activity of cells were largely arrested and nearly no RLEC was seen on the posterior capsule (P<0.05). Control group had no effect on structure and proliferative activity of RLEC, and the growth proceeded rapidly so that the posterior capsule were totally covered by a confluent monolayer of cell by the end of 7 days. Under TEM, the cells in the control group were tightly arrayed with clearly defined cellular boundary and structure; while cellular deformity and undefined intracellular structure could be seen in the 0.4g/L and 0.8g/L experimental groups. CONCLUSION: PGMS can effectively inhibit the proliferation of RLEC.