Sediment geochemical records of water quality deterioration in lake Jiren, a remote alpine lake on the southeastern margin of the Tibetan Plateau.

Limited human activities in catchments make remote alpine lakes valuable sites for studying the evolution of lake environments in response to climate change and atmospheric deposition; however, this issue remains rarely studied owing to the scarcity of monitoring data. In this study, water quality evolution in Lake Jiren, a remote alpine lake on the southeastern margin of the Tibetan Plateau, over the past two centuries was reconstructed through geochemical analyses of aliphatic hydrocarbons, major and trace elements, and organic matter (OM) pyrolysis products in a dated sediment core, and the associated drivers were identified by temporally comparing the geochemical results with document records. All geochemical data demonstrated that the lake water remained relatively pure until 1947, after which the n-alkane and αß-hopane proxies indicated eutrophication and petroleum contamination. The OM pyrolysis proxy hydrocarbon index indicated more eutrophic conditions after 1957. Concurrently, hypolimnetic deoxygenation increased, as indicated by redox-sensitive proxies, such as the enrichment factors (EFs) of molybdenum (Mo). These proxies recorded further intensification of deoxygenation after 1976. The EFs for other trace elements indicated cadmium contamination after 1967. The greater anthropogenic emissions of reactive nitrogen, petroleum products, and heavy metals in East and South Asia since approximately 1950 and the subsequent atmospheric transport of these materials to the lake might be the basic driver of water quality deterioration. Eutrophication induced by nitrogen deposition was responsible for increased hypolimnetic deoxygenation by enhancing phytoplankton productivity and OM input. The further intensification of deoxygenation was attributed to climate warming since the 1970s, as prolonged water column stratification under this condition decreased oxygen input from the epilimnion to the lake bottom. These findings may be beneficial for understanding the natural and anthropogenic effects on the water quality of alpine lakes and help in the environmental management of Lake Jiren and other alpine lakes.

Target Embolization Combined with Multimodal Thermal Ablation for Solid Tumors by Smart Poly(amino acid)s Nanocomposites.

Noninterventional embolization does not require the use of a catheter, and the treatment of solid tumors in combination with thermal ablation can avoid some of the risks of the surgical procedure. Therefore, we developed an efficient tumor microenvironment-gelled nanocomposites with poly [(l-glutamic acid-ran-l-tyrosine)-b-l-serine-b-l-cysteine] (PGTSCs) coated-nanoparticles (Fe3O4&Au@PGTSCs), from which the prepared PGTSCs were given possession of pH response to an acidic tumor microenvironment. Fe3O4&Au@PGTSC in noninterventional embolization treatment not only achieved the smart targeted medicine delivery but also meshed with noninvasive multimodal thermal ablation therapy and multimodal imaging of solid tumors via intravenous injection. It was worth noting that the results of animal experiments in vivo demonstrated that Fe3O4&Au@PGTSCs have specific tumor accumulation and embolization and thermal ablation effects; at 10 days postinjection, only scars were found at the tumor site. After 20 days, the tumors of model mice completely disappeared. This device is easier to treat solid tumors based on the slightly acidic tumor environment.

A Simple and Efficient Embolization-Combined Therapy for Solid Tumors by Smart Poly(amino acid)s Nanocomposites.

Interventional embolization and minimally invasive thermal ablation are common clinical methods for treatment of unresectable solid tumors, but they both have many insurmountable disadvantages. Inspired by pH-responsive drug delivery systems, we report the tumor microenvironment-gelled nanocomposites with poly[(l-glutamic acid-ran-l-tyrosine)-b-l-threonine-b-l-cysteine]s (PGTTCs) coating nanoparticles (NPs, Au or Fe3O4) for noninterventional targeted embolization combined with noninvasive thermal ablation therapy of solid tumors by intravenous injection without catheter use. The results of the animal trial in vivo with tumor-bearing mice and rabbits showed superior targeted embolization and therapy and fluorescence/single-photon emission computed tomography/magnetic resonance multimodal imaging effects. Tumors treated with NPs@PGTTCs were shrunken and necrotized within 30 days, the long-term survival rate was more than 80%, and the same effects can be achieved within 15 days when combined with thermal ablation. The method is so simple and efficient for many hard-to-treat tumors within an acidic microenvironment, which is not only a great improvement and innovation in tumor theranostics but also an important development in nanomedicine.

Geochemical records of Lake Erhai (South-Western China) reveal the anthropogenically-induced intensification of hypolimnetic anoxia in monomictic lakes.

In monomictic lakes, hypolimnetic anoxia is becoming severe in extent and duration over the past few decades. Understanding historical trends in hypolimnetic dissolved oxygen (DO) levels and the factors controlling them is crucial for effective protection and management of monomictic lakes everywhere, but the issue remains little studied in China. Here, our study elucidated the variation of hypolimnion DO and organic matter (OM) input in Lake Erhai (a typical monomictic lake in South-Western China) during the past 200 years, by using the geochemical profiles of elements (C, N, P, S, Mo, Ca, and Al) and aliphatic hydrocarbons in a dated sediment core. The values of element proxies (S concentrations, S/Al ratios, Mo enrichment factor, and total organic carbon/total P ratios) and pristane/phytane (Pr/Ph) ratios reflect relatively limited development of anoxia in the lake hypolimnion before 1990. Meanwhile, the n-alkane proxies (short-chain, middle-chain, and long-chain n-alkane abundances, n-C17/n-C16 alkane ratios, and Paq) indicate relatively scant inputs of OM from phytoplankton and relatively high inputs of OM from terrestrial plants or from submerged macrophytes. Taken together the results show that OM supplied in this period did not deteriorate hypolimnion DO in Lake Erhai. The element proxies and Pr/Ph ratios point to that the lake had experienced a pronounced intensification of hypolimnetic anoxia after 1990, and the n-alkane proxies indicate that the lake was susceptible to severe eutrophication and phytoplankton blooms in this period. The synchronous sharp variation implies the decay of massive phytoplankton OM had severely consumed oxygen in the lake hypolimnion. The large surface area/depth ratio in Lake Erhai is conducive for an overturn of the water column during wind disturbance, which allowed the water column stratification and relating effects (e.g., hypolimnetic anoxia) less vulnerable to some aspects of climate change.

Smart-Polypeptide-Coated Mesoporous Fe3O4 Nanoparticles: Non-Interventional Target-Embolization/Thermal Ablation and Multimodal Imaging Combination Theranostics for Solid Tumors.

Tumor theranostics hold great potential for personalized medicine in the future, and transcatheter arterial embolization (TAE) is an important clinical treatment for unresectable or hypervascular tumors. In order to break the limitation, simplify the procedure of TAE, and achieve ideal combinatorial theranostic capability, here, a kind of triblock-polypeptide-coated perfluoropentane-loaded mesoporous Fe3O4 nanocomposites (PFP-m-Fe3O4@PGTTCs) were prepared for non-interventional target-embolization, magnetic hyperthermia, and multimodal imaging combination theranostics of solid tumors. The results of systematic animal experiments by H22-tumor-bearing mice and VX2-tumor-bearing rabbits in vivo indicated that PFP-m-Fe3O4@PGTTC-6.3 has specific tumor accumulation and embolization effects. The tumors' growth has been inhibited and the tumors disappeared 4 weeks and ≤15 days post-injection with embolization and magnetic hyperthermia combination therapy, respectively. The results also showed an excellent effect of magnetic resonance/ultrasound/SPECT multimodal imaging. This pH-responsive non-interventional embolization combinatorial theranostics system provides a novel embolization and multifunctional theranostic candidate for solid tumors.

The role of Se content in improving anti-tumor activities and its potential mechanism for selenized Artemisia sphaerocephala polysaccharides.

Drawing an instructive point on the correlation between Se content and anti-tumor effects is helpful to develop Se-polysaccharides with potential anti-tumor activities. In this work, Se content-related anti-tumor activities are assessed in vitro by multiple comparisons among Na2SeO3, Artemisia sphaerocephala polysaccharide (ASP), and selenized ASP (SeASPs, Se contents 4344-13 030 µg g-1) synthesized by a chemical modification method. The results suggest that SeASPs exhibit potent anti-proliferation activities against three kinds of tumor cells by inducing apoptosis and cell cycle arrest, which is positively correlated to Se content. Meanwhile, SeASPs display low cytotoxicity against normal cells as compared with Na2SeO3 and 5-FU. A mitochondrial membrane potential assay and western blotting analysis suggest that the SeASPs induce HepG2 cell apoptosis via mitochondrial and death receptor pathways, which is confirmed by the reduced mitochondrial membrane potential, upregulated Bax/Bcl-2 ratio, promoted Cyt C release, and increased expression level of caspase-3/-9/-8. In an in vivo anti-tumor assay, SeASP with a high Se content (13 030 µg g-1) also obviously inhibits H22 tumor growth in a dose-dependent manner, and a tumor suppression rate of 45.10% is observed. In addition, the results of ELISA analysis suggest that SeASPs obviously increase the concentration of serum NO, cytokines (IL-1ß, IL-6, TNF-α), and Ig-G in a dose-dependent manner as compared with the control and ASP group. It could be concluded that adjusting the Se content might be an effective approach to improve the anti-tumor activities of Se-polysaccharides.

[HNMP]HSO4 catalyzed synthesis of selenized polysaccharide and its immunomodulatory effect on RAW264.7 cells via MAPKs pathway.

In this paper, selenized Artemisia sphaerocephala polysaccharides (SePAS) were obtained through employing N-methyl-2-pyrrolidone hydrosulfate as catalyst, which showed a maximum Se content enhanced to 8744 µg/g. FT-IR, 1D/2D NMR, X-ray photoelectron spectroscopy (XPS) and size-exclusion chromatograph analysis exhibited that Se had been successfully introduced into PAS and existed in the form of selenate group (Se4+) with the substitution position at C-6. Furthermore, immunostimulating assays indicated that SePAS with high Se content exhibited stronger immunomodulatory activities by upregulated the phosphorylation level of ERK, JNK and p38, thus enhancing RAW264.7 cells proliferation, phagocytosis, levels of interleukin-6, nitric oxide, tumor necrosis factor and interleukin-1ß. The current outcome suggested that Se content might be a critical factor affecting the immunomodulatory effects of selenized PAS on macrophage RAW264.7.

Long-term changes of water quality in aquaculture-dominated lakes as revealed by sediment geochemical records in Lake Taibai (Eastern China).

The rapid development and exploitation of the Yangtze River basin in order to ensure human food security and increase living space in recent decades has resulted in significant potential for degradation of water quality in the river and in hundreds of lakes. Understanding how lake environments have evolved to their present state under a variety of external influences is crucial for evaluating their current status and anticipating future scenarios of environmental changes. However, the lakes along the middle reaches of the Yangtze River (MRY) are as yet little studied. Here, we described the long-term anthropogenic environmental transformations of a small lake (Lake Taibai) in the MRY area, based on a detailed quantitative geochemical analysis of the aliphatic hydrocarbons, nutrients (N and P), biogenic silica (BSi), and major and trace elements present in a dated sediment core retrieved from the lake. Our data revealed that levels of short-chain n-alkanes, αß-hopanes and the trace elements arsenic (As) and cadmium (Cd) were all low for the entire record in sediments prior to ca. 1970, reflecting unpolluted natural state of the lake. Pronounced anthropogenic effects began to appear in sediments deposited in the subsequent years ca. 1970-1990, during which the levels of all these components were elevated, most likely driven by input of nitrogen (N) and phosphorus (P) containing chemical fertilizers, pesticides and diesel oil respectively. Since ca. 1990, changes of short-chain n-alkane levels in the sediment suggested the lake had undergone dramatic eutrophication in which existing anthropogenic stressors were exacerbated by technological advances that extended the use of chemical fertilizer into aquaculture. This pattern contrasted with an otherwise comparable lake in the lower Yangtze River basin, Lake Changdang, in which trace element and petroleum pollution were much more prominent due to dramatic urbanization and industrialization of the catchment.

Anthropogenically driven differences in n-alkane distributions of surface sediments from 19 lakes along the middle Yangtze River, Eastern China.

During the past few decades, the Yangtze River basin has undergone massive anthropogenic change. In order to evaluate the impacts of human interventions on sediment n-alkanes of lakes across this region, the aliphatic hydrocarbon fractions of 19 surface sediment samples collected from lakes along the middle reaches of the Yangtze River (MYR) were analyzed using gas chromatography-mass spectrometry. The n-alkanes extracted from the sediments contained a homologous series from C15 to C34, with a notable predominance of odd carbon compounds except for sediments from the more intensively industrialized Lake Daye, in which > C21 n-alkanes showed no odd/even predominance, and carbon preference index (CPI) approached unity. Abundance values of middle-chain (C21, C23, and C25) and long-chain (C27, C29, C31, and C33) n-alkanes in Lake Daye were approximately 4 to 3 times greater than the average for other lakes, reaching 272.4 and 486.3 µg/g TOC, respectively, in the study. Short-chain n-alkanes (C15, C17, and C19) in the sediments varied in abundance from 10.0 to 76.2 µg/g TOC across the study and showed a moderate correlation with total phosphorus (TP) concentrations in the overlying water. The results indicated anthropogenic eutrophication enhanced the accumulation of short-chain n-alkanes in sediments because the primary producers in which they are synthesized are highly susceptible to nutrient forcing. Middle-chain n-alkane abundances were less affected by eutrophication and generally enriched in macrophyte lakes, while long-chain n-alkanes tend to be low in sediments from more eutrophic water. In the case of Lake Daye, direct discharges of petroleum products from heavy industry have introduced quantities of petroleum n-alkanes (> C21), far exceeding the amounts of biogenic input, and the sediment > C21 n-alkanes detected in this study showed typical characteristics of petroleum source. In other lakes, inputs of petroleum products from surface runoff of vehicle/traffic emissions associated with urbanization and economic growth contributed comparatively few n-alkanes to sediments, resulting in declines in CPI for > C21 n-alkanes, most obviously in Lakes Huanggai, Donghu, and Futou. Calculated CPI values suggest that a major proportion of the n-alkanes present in these lakes are derived from biogenic input. The results of this study provided evidences that n-alkane profiles of lake sediments respond sensitively to human-induced eutrophication and different sources of petroleum pollution.

Fish-mediated plankton responses to increased temperature in subtropical aquatic mesocosm ecosystems: Implications for lake management.

Although it is well established that climate warming can reinforce eutrophication in shallow lakes by altering top-down and bottom-up processes in the food web and biogeochemical cycling, recent studies in temperate zones have also shown that adverse effects of rising temperature are diminished in fishless systems. Whereas the removal of zooplanktivorous fish may be useful in attempts to mitigate eutrophication in temperate shallow lakes, it is uncertain whether similar mitigation might be achieved in warmer climates. We compared the responses of zooplankton and phytoplankton communities to climate warming in the presence and absence of fish (Aristichthys nobilis) in a 4-month mesocosm experiment at subtropical temperatures. We hypothesized that 1) fish and phytoplankton would benefit from warming, while zooplankton would suffer in fish-present mesocosms and 2) warming would favor zooplankton growth but reduce phytoplankton biomass in fish-absent mesocosms. Our results showed significant interacting effects of warming and fish presence on both phytoplankton and zooplankton. In mesocosms with fish, biomasses of fish and phytoplankton increased in heated treatments, while biomasses of Daphnia and total zooplankton declined. Warming reduced the proportion of large Daphnia in total zooplankton biomass, and reduced the zooplankton to phytoplankton biomass ratio, but increased the ratio of chlorophyll a to total phosphorus, indicating a relaxation of zooplankton grazing pressure on phytoplankton. Meanwhile, warming resulted in a 3-fold increase in TP concentrations in the mesocosms with fish present. The results suggest that climate warming has the potential to boost eutrophication in shallow lakes via both top-down (loss of herbivores) and bottom-up (elevated nutrient) effects. However, in the mesocosms without fish, there was no decline in large Daphnia or in total zooplankton biomass, supporting the conclusion that fish predation is the major driver of low large Daphnia abundance in warm lakes. In the fishless mesocosms, phytoplankton biomass and nutrient levels were not affected by temperature. Our study suggests that removing fish to mitigate warming effects on eutrophication may be potentially beneficial in subtropical lakes, though the rapid recruitment of fish in such lakes may present a challenge to success in the long-term.

Sulfation can enhance antitumor activities of Artemisia sphaerocephala polysaccharide in vitro and vivo.

In this study, a sulfated Artemisia sphaerocephala polysaccharide (ASPs) was prepared and its antitumor activity was evaluated in tumor cells and Hepatoma 22 (H22) tumor-bearing mice. In vitro experiments, ASPs significantly inhibited the growth of HepG2 and Hela cells with the IC50 values of 172.03 and 161.42µg/mL, respectively. Moreover, no direct cytotoxicity against mouse fibroblast L929 normal cells was observed in vitro. After oral administration for 12days, the tumor growth was significantly suppressed by ASPs at the doses of 200mg/kg (inhibition rate of 60.85%). Results of tumor histological morphology and cell cycle analysis showed that ASPs could arrest H22 cells at S phase and promote cell apoptosis. Additionally, immunohistochemical analysis demonstrated that ASPs caused the down-regulation of mutant p53 protein expression in a dose-dependent manner. Therefore, these findings proposed new insight into antitumor properties of sulfated polysaccharide as a promising agent in cancer treatment.

Sediment lipid biomarkers record phytoplankton dynamics of Lake Heihai (Yunnan Province, SW China) driven by climate warming since the 1980s.

Increased phosphorus (P) export from sediments to the overlying water column is a significant factor driving the variation of phytoplankton in productivity and community structure in lakes. However, the lack of long-term instrumental data often impeded analyses attempting to associate dynamics of phytoplankton with variation of internal P loading. Here, elements and lipid biomarkers were analyzed in a sediment core from Lake Heihai, a small, deep, and ultraoligotrophic alpine lake in Haba Mountain, Yunnan Province, SW China. The data document incredible enrichment of element iron (Fe) in the sediment, whose concentrations are much higher than those of other common major elements including titanium (Ti), aluminum (Al), calcium (Ca), and magnesium (Mg). This finding, together with the abundance correlation between P and Fe (n = 30, R 2  = 0.783) suggested that P was probably retained in sediments through sorption with micro-layer of FeOOH at the sediment-water interface. The P/Ti ratios, P/Fe ratios, and P/total organic carbon (TOC) ratios all declined in the sediment since 1980, perhaps indicating increased P release from sediments to the overlying water column initiated by hypolimnion anoxia and sulfidic, which is presumably triggered by regional climate warming since the 1980s. The P-rich bottom water can be injected into photic zone during wind-driven mixing and overturn of the water column, although its frequency and intensity might decline due to stronger water column stratification in warming climate. In response, diatoms exhibited a rapid increase of productivity at this time, because diatoms have a storage vacuole and thereby nutrients such as P can be concentrated and used for cell division long after they are depleted in the bulk fluid. Elevated diatom biomass produced shading of light penetration, allowing for a low productivity for dinoflagellates. This study deepens our understanding of the impact of climate warming on lake systems and highlights the element biogeochemical cycle contributing to the variation of nutrients in the lake water column.

[Case-control study on manipulation combined with Chinese herbs for the treatment of lumbar disc herniation within chronic stage].

OBJECTIVE: To observe and compare the therapeutic effects of two methods to lumbar disc herniation treated by manipulation combined with Chinese herbs and traction with Western medicine. METHODS: A multi-center with a central district unit was used to study the patients with lumbar disc herniation from November 28th, 2008 to May 7th, 2010. All the patients were divided into treatment group and control group. The treatment group had 100 cases, including 45 males and 55 females, averaged (43.43 +/- 9.18) years. The treatment group was treated by manipulation combined with Chinese herbs; Control group had 100 cases (5 cases were fall off), including 38 males and 57 females, averaged (42.29 +/- 9.78) years. The control group was treated by traction with Western medicine. The course of treatment was 3 weeks. VAS, M-JOA, LMS (lower limb muscle strength) and classification efficacy was used to evaluate outcome and therapeutic effects before and after treatment. RESULTS: VAS and M-JOA were improved after the treatment both in treatment group and control group; there was no significant difference in LMS before and after treatment in both groups. VAS and M-JOA in treatment group was superior to those of control group after treatment. There was no significant difference in LMS. According to classification efficacy, 41 cases got excellent result, 34 good, 13 fair and 12 poor in treatment group; in control group, 35 cases obtained excellent results, 16 good, 19 fair and 25 poor. The effect of treatment group was better than that of control group. CONCLUSION: Both of two methods can improve the score of VAS, M-JOA, and treatment group is better than that of control group. While for the improvement of LMS, both of two methods have no obvious effects.

[Study on the progress of the mechanism of TGF-beta in the scarring and the effect of TCM].

Transforming growth factor (TGF-beta) plays a central role in wound healing and scarring. TGF-beta is a member of cytokine family, involving cell proliferation, migration, differentiation and apoptosis, which subsequently trigger extracellular matrix (ECM) deposite and collagen overproduction. A number of regulators of TGF-beta expression bave been identified, including Decorin CTGF, etc. TCM can reduced later scarring, and it accelerates wound healing. TCM can reduce the expression of TGF-beta, resistance of fibrosis, so that lighten the development of scar. This article reviewed the mechanism of TGF-beta in the scarring and TCM can decrease the development of scar effected by TGF-beta.

Effect of anemonin on NO, ET-1 and ICAM-1 production in rat intestinal microvascular endothelial cells.

Anemonin (the dilactone of cyclobutane-1, 2-diol-1, 2-diacrylic acid) was isolated from the root of Pulsatilla chinensis Regel. Pulsatilla chinensis Regel has been used in the treatment of enteritis in China for years. However, only little was known about the mechanism underlying its anti-inflammatory effects. We investigated the effect of anemonin on the release of nitric oxide (NO), endothelin-1 (ET-1) and soluble intercellular adhesion molecule-1 (sICAM-1) induced by lipopolysaccharide (LPS) in primary cultures of rat intestinal microvascular endothelial cells (RIMECs). RIMECs were challenged with 1 microg/ml LPS with or without the presence of various concentrations of anemonin (1, 5 and 10 microg/ml). Anemonin significantly inhibited the production of NO and ET-1 induced by LPS at a concentration of 5 microg/ml and at 10 microg/ml anemonin down-regulated LPS-induced sICAM-1 expression. Anemonin itself had no effect on either factor. These findings suggest that anemonin may exert some beneficial therapeutic action in intestinal inflammation, at least in part by inhibiting the production of NO, ET-1 and ICAM-1 in RIMECs and thus preventing intestinal microvascular dysfunction.