Highly selective photoelectrochemical CO2 reduction by crystal phase-modulated nanocrystals without parasitic absorption.

Photoelectrochemical (PEC) carbon dioxide (CO2) reduction (CO2R) holds the potential to reduce the costs of solar fuel production by integrating CO2 utilization and light harvesting within one integrated device. However, the CO2R selectivity on the photocathode is limited by the lack of catalytic active sites and competition with the hydrogen evolution reaction. On the other hand, serious parasitic light absorption occurs on the front-side-illuminated photocathode due to the poor light transmittance of CO2R cocatalyst films, resulting in extremely low photocurrent density at the CO2R equilibrium potential. This paper describes the design and fabrication of a photocathode consisting of crystal phase-modulated Ag nanocrystal cocatalysts integrated on illumination-reaction decoupled heterojunction silicon (Si) substrate for the selective and efficient conversion of CO2. Ag nanocrystals containing unconventional hexagonal close-packed phases accelerate the charge transfer process in CO2R reaction, exhibiting excellent catalytic performance. Heterojunction Si substrate decouples light absorption from the CO2R catalyst layer, preventing the parasitic light absorption. The obtained photocathode exhibits a carbon monoxide (CO) Faradaic efficiency (FE) higher than 90% in a wide potential range, with the maximum FE reaching up to 97.4% at -0.2 V vs. reversible hydrogen electrode. At the CO2/CO equilibrium potential, a CO partial photocurrent density of -2.7 mA cm-2 with a CO FE of 96.5% is achieved in 0.1 M KHCO3 electrolyte on this photocathode, surpassing the expensive benchmark Au-based PEC CO2R system.

Polysaccharide assemblies in fungal and plant cell walls explored by solid-state NMR.

Structural analysis of macromolecular complexes within their natural cellular environment presents a significant challenge. Recent applications of solid-state NMR (ssNMR) techniques on living fungal cells and intact plant tissues have greatly enhanced our understanding of the structure of extracellular matrices. Here, we selectively highlight the most recent progress in this field. Specifically, we discuss how ssNMR can provide detailed insights into the chemical composition and conformational structure of pectin, and the consequential impact on polysaccharide interactions and cell wall organization. We elaborate on the use of ssNMR data to uncover the arrangement of the lignin-polysaccharide interface and the macrofibrillar structure in native plant stems or during degradation processes. We also comprehend the dynamic structure of fungal cell walls under various morphotypes and stress conditions. Finally, we assess how the combination of NMR with other techniques can enhance our capacity to address unresolved structural questions concerning these complex macromolecular assemblies.

A pectin methyltransferase modulates polysaccharide dynamics and interactions in Arabidopsis primary cell walls: Evidence from solid-state NMR.

Plant cell walls contain cellulose embedded in matrix polysaccharides. Understanding carbohydrate structures and interactions is critical to the production of biofuel and biomaterials using these natural resources. Here we present a solid-state NMR study of cellulose and pectin in 13C-labeled cell walls of Arabidopsis wild-type and mutant plants. Using 1D 13C and 2D 13C-13C correlation experiments, we detected a highly branched arabinan structure in qua2 and tsd2 samples, two allelic mutants for a pectin methyltransferase. Both mutants show close physical association between cellulose and the backbones of pectic homogalacturonan and rhamnogalacturonan-I. Relaxation and dipolar order parameters revealed enhanced microsecond dynamics due to polymer disorder in the mutants, but restricted motional amplitudes due to tighter pectin-cellulose associations. These molecular data shed light on polymer structure and packing in these two pectin mutants, helping to elucidate how pectin could influence cell wall architecture at the nanoscale, cell wall mechanics, and plant growth.

[Observation of acupoint application of gel plaster on insomnia].

OBJECTIVE: To observe the effect of acupoint application of gel plaster on quality of sleep and life in patients with insomnia. METHODS: A total of 63 patients with insomnia were randomized into a gel plaster group (32 cases, 1 case dropped off) and a placebo plaster group (31 cases). Acupoint application of gel plaster was applied at Yintang (GV 29) and Yongquan (KI 1) in the gel plaster group, placebo plaster was applied at the same acupoints in the placebo plaster group. The treatment was given from bedtime to early moming of the next day, 5 days were as one course, with 2-day interval, totally 4 courses were required in the both groups. Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS) and Flinders fatigue scale were used to evaluate the sleep quality and fatigue level of the patients in the both groups before and after treatment and at 2 weeks of follow-up. The variations of insomnia TCM syndrome score and the 36-item short-form health survey (SF-36) score before and after treatment were observed. RESULTS: Compared before treatment, the scores of PSQI, ESS and FFS after treatment and at follow-up were decreased in the both groups (P<0.01), and the variations of PSQI total scores and ESS scores in the gel plaster group were larger than those in the placebo plaster group (P<0.05). Compared before treatment, the insomnia TCM syndrome scores were decreased (P<0.01), the scores of physiological function, physiological role, general health, role emotion, mental health of SF-36 were improved after treatment in the both groups (P<0.05), and the social function score after treatment in the gel plaster group was superior to that in the placebo plaster group (P<0.05). CONCLUSION: Acupoint application of gel plaster can effectively improve the quality of sleep and life in patients with insomnia.

[Bibliometric analysis of refractory facial paralysis based on CNKI database].

The current development situation and the hotspot of the relevant research on refractory facial paralysis are explored. The articles on refractory facial paralysis are retrieved from CNKI database. The bibliographic items co-occurrence matrix builder (BICOMB) 2.0 is adopted to extract and analyze statistically literature characteristics and generate the high-frequency keywords matrix. The graphical clustering toolkit (gCLUTO) 1.0 is used to cluster the high-frequency keywords. A total of 750 articles are included, mostly published in Journal of Clinical Acupuncture and Moxibustion (63 articles), Chinese Acupuncture & Moxibustion (54 articles) and Shanghai Journal of Acupuncture and Moxibustion (27 articles) separately. The number of published articles by the active first authors are accounted for 10.1% of the total. When the high-frequency keywords are clustered into 4 categories, the topics with good cluster effect including the inheritance of the experiences of famous doctors in the comprehensive treatment of refractory facial paralysis, the comprehensive treatment measures with the a quite high curative effect on refractory facial paralysis based on heat-sensitive moxibustion and those based on the intervention by enhancing acupoint stimulation effect, as well as the study on the comprehensive treatment measures. General speaking, the regimen of acupuncture and moxibustion is a hotspot in the study on refractory facial paralysis. Research fellows give the consideration on the inheritance of the experiences of famous doctors, adopt the comprehensive treatment methods and enhance the actions of "warming" and "promoting" in the regimen by focusing on the pathogenesis. Such an idea has certain enlightening role to the study on the treatment of refractory diseases.

[Needle-embedding treatment for hemifacial spasm: research progress].

The articles regarding needle-embedding treatment for hemifacial spasm published before September 30, 2019 were searched from SinoMed, Wanfang, CNKI, VIP and PubMed database, and were analyzed and summarized from treatment methods, acupoint selection, stage differentiation and action mechanism. As a result, 45 Chinese articles were obtained. The needle-embedding treatment was divided into intradermal needling and acupoint thread-embedding; the top five acupoints were Sibai (ST 2), Taiyang (EX-HN 5), Dicang (ST 4), Jiache (ST 6) and spasm trigger points. The basic research of needle-embedding treatment for hemifacial spasm is weak, and the literature regarding stage differentiation is insufficient, which are in need of further study.

Simultaneously promoted reactive manganese species and hydroxyl radical generation by electro-permanganate with low additive ozone.

A novel water treatment process combining electrolysis, permanganate and ozone was tested in the laboratory. The combination showed synergistic effects in degrading various organic contaminants (like diclofenac, sulfamethoxazole, carbamazepine, etc.). A small amount of O3 (1 mg L-1, 60 mL min-1) significantly improved the oxidation and mineralization ability of an electro-permanganate process by generating more reactive manganese species and hydroxyl radicals. The combination required less energy consumption than comparable processes. Mechanism experiments showed that the ·OH involved was mainly generated by cathode reduction, homogeneous manganese catalysis, and heterogeneous manganese catalysis of O3 decomposition. Reactive Mn species were generated by electro-reduction, ·OH oxidation or/and O3 activation. In situ generated Mn (Ⅳ)s plays a vital role in generating ·OH and reactive Mn species. ·OH generated by O3 catalysis could transfer colloid Mn (Ⅳ)s to free Mn (Ⅴ)aq and Mn (Ⅵ) aq. And both the ·OH and RMnS played the dominant role for DCF removal. Increasing permanganate dosage, O3 concentration, the current density, Cl-, or humic acid, and decreasing the pH all enhanced the degradation of diclofenac, but the presence of PO43- or HCO3- inhibited it. Supplementing electrolysis with permanganate and O3 might be a practical, sustainable, and economical technology for treating refractory organics in natural waters.

Mutations in the Pectin Methyltransferase QUASIMODO2 Influence Cellulose Biosynthesis and Wall Integrity in Arabidopsis.

Pectins are abundant in the cell walls of dicotyledonous plants, but how they interact with other wall polymers and influence wall integrity and cell growth has remained mysterious. Here, we verified that QUASIMODO2 (QUA2) is a pectin methyltransferase and determined that QUA2 is required for normal pectin biosynthesis. To gain further insight into how pectin affects wall assembly and integrity maintenance, we investigated cellulose biosynthesis, cellulose organization, cortical microtubules, and wall integrity signaling in two mutant alleles of Arabidopsis (Arabidopsis thaliana) QUA2, qua2 and tsd2 In both mutants, crystalline cellulose content is reduced, cellulose synthase particles move more slowly, and cellulose organization is aberrant. NMR analysis shows higher mobility of cellulose and matrix polysaccharides in the mutants. Microtubules in mutant hypocotyls have aberrant organization and depolymerize more readily upon treatment with oryzalin or external force. The expression of genes related to wall integrity, wall biosynthesis, and microtubule stability is dysregulated in both mutants. These data provide insights into how homogalacturonan is methylesterified upon its synthesis, the mechanisms by which pectin functionally interacts with cellulose, and how these interactions are translated into intracellular regulation to maintain the structural integrity of the cell wall during plant growth and development.

Predictive Big Data Analytics using the UK Biobank Data.

The UK Biobank is a rich national health resource that provides enormous opportunities for international researchers to examine, model, and analyze census-like multisource healthcare data. The archive presents several challenges related to aggregation and harmonization of complex data elements, feature heterogeneity and salience, and health analytics. Using 7,614 imaging, clinical, and phenotypic features of 9,914 subjects we performed deep computed phenotyping using unsupervised clustering and derived two distinct sub-cohorts. Using parametric and nonparametric tests, we determined the top 20 most salient features contributing to the cluster separation. Our approach generated decision rules to predict the presence and progression of depression or other mental illnesses by jointly representing and modeling the significant clinical and demographic variables along with the derived salient neuroimaging features. We reported consistency and reliability measures of the derived computed phenotypes and the top salient imaging biomarkers that contributed to the unsupervised clustering. This clinical decision support system identified and utilized holistically the most critical biomarkers for predicting mental health, e.g., depression. External validation of this technique on different populations may lead to reducing healthcare expenses and improving the processes of diagnosis, forecasting, and tracking of normal and pathological aging.

Effects of Pectin Molecular Weight Changes on the Structure, Dynamics, and Polysaccharide Interactions of Primary Cell Walls of Arabidopsis thaliana: Insights from Solid-State NMR.

Significant cellulose-pectin interactions in plant cell walls have been reported recently based on 2D 13C solid-state NMR spectra of intact cell walls, but how these interactions affect cell growth has not been probed. Here, we characterize two Arabidopsis thaliana lines with altered expression of the POLYGALACTURONASE INVOLVED IN EXPANSION1 (PGX1) gene, which encodes a polygalacturonase that cleaves homogalacturonan (HG). PGX1AT plants overexpress PGX1, have HG with lower molecular weight, and grow larger, whereas pgx1-2 knockout plants have HG with higher molecular weight and grow smaller. Quantitative 13C solid-state NMR spectra show that PGX1AT cell walls have lower galacturonic acid and xylose contents and higher HG methyl esterification than controls, whereas high molecular weight pgx1-2 walls have similar galacturonic acid content and methyl esterification as controls. 1H-transferred 13C INEPT spectra indicate that the interfibrillar HG backbones are more aggregated whereas the RG-I side chains are more dispersed in PGX1AT cell walls than in pgx1-2 walls. In contrast, the pectins that are close to cellulose become more mobile and have weaker cross peaks with cellulose in PGX1AT walls than in pgx1-2 walls. Together, these results show that polygalacturonase-mediated plant growth is accompanied by increased esterification and decreased cross-linking of HG, increased aggregation of interfibrillar HG, and weaker HG-cellulose interactions. These structural and dynamical differences give molecular insights into how pectins influence wall dynamics during cell growth.

High-Performance Hydrogen Evolution from MoS2(1-x) P(x) Solid Solution.

A MoS2(1-x) P(x) solid solution (x = 0 to 1) is formed by thermally annealing mixtures of MoS2 and red phosphorus. The effective and stable electrocatalyst for hydrogen evolution in acidic solution holds promise for replacing scarce and expensive platinum that is used in present catalyst systems. The high performance originates from the increased surface area and roughness of the solid solution.

Solid-state NMR investigations of cellulose structure and interactions with matrix polysaccharides in plant primary cell walls.

Until recently, the 3D architecture of plant cell walls was poorly understood due to the lack of high-resolution techniques for characterizing the molecular structure, dynamics, and intermolecular interactions of the wall polysaccharides in these insoluble biomolecular mixtures. We introduced multidimensional solid-state NMR (SSNMR) spectroscopy, coupled with (13)C labelling of whole plants, to determine the spatial arrangements of macromolecules in near-native plant cell walls. Here we review key evidence from 2D and 3D correlation NMR spectra that show relatively few cellulose-hemicellulose cross peaks but many cellulose-pectin cross peaks, indicating that cellulose microfibrils are not extensively coated by hemicellulose and all three major polysaccharides exist in a single network rather than two separate networks as previously proposed. The number of glucan chains in the primary-wall cellulose microfibrils has been under active debate recently. We show detailed analysis of quantitative (13)C SSNMR spectra of cellulose in various wild-type (WT) and mutant Arabidopsis and Brachypodium primary cell walls, which consistently indicate that primary-wall cellulose microfibrils contain at least 24 glucan chains.

[Effects of electro-acupuncture on neuronal apoptosis and associative function in rats with spinal cord injury].

OBJECTIVE: To explore the effect of electro-acupuncture to improve the bladder function after acute spinal cord injury in rats and its possible mechanism. METHODS: Sixty healthy adult male SD rats of SPF grade, with body weight of 220 to 250 g, one week after feeding adaptation, were randomly divided into sham operation group, model group, electro-acupuncture group, electro-acupuncture control group with 15 rats in each group. Sham operation group underwent no stimulation, and the moderate damage model of spinal cord injury were made in other three groups according to modified Allens method. The model group were not treated, electro-acupuncture group were treated with electro-acupuncture on Zhibianxue and Shuidaoxue, and electro-acupuncture control group were treated with electro-acupuncture on 0.5 inch next to Zhibianxue and Shuidaoxue. The frequency of 2/100 Hz, current of 1 mA, stimulation time of 15 min, once a day, left and right alternately stimulate every time, for a total of 7 times. The changes of residual urine volume and urine output in rats at the 1st and the 7th days after operation were observed. And 7 d later, the rats were sacrificed and the injured spinal cord were taken out to observe the apoptosis, and to detect the changes of Bcl-2, Bax, Bad content. RESULTS: After modeling,the rats of three groups showed different bladder dysfunction. In electro-acupuncture group and electro-acupuncture control group, the residual urine volume of the 7th day after operation was significant lower than the 1st day after operation (P < 0.001), and there was statistically significant difference on the 7th day after operation between two groups (P < 0.001). Compared with model group, the urine output of electro-acupuncture group and electro-acupuncture control group was significantly increased on the 7th day after operation, and there was sig- nificant difference between electro-acupuncture group and electro-acupuncture control group (P < 0.001). Electro-acupuncture can inhibit apoptosis of spinal cord neurons by TUNEL detection. Postoperative at 7 d, the rate of nerve cell apoptosis in electro -acupuncture group and electro-acupuncture control group was significant increased than model group (P < 0.01, P < 0.05), and there was significant difference between electro-acupuncture group and electro-acupuncture control group (P < 0.005). Compared with model group, the positive expression rate of Bax, Bad decreased (P < 0.01, P < 0.05), and Bcl-2 increased (P < 0.01) in electro-acupuncture group and electro-acupuncture control group,there was significant difference between electro-acupuncture group and electro-acupuncture control group (P < 0.01). CONCLUSION: Electro-acupuncture can obviously promote the repair of acute spinal cord injury,its mechanism may be through increasing Bcl-2, inhibiting the expression of Bax, Bad, which inhibits the apoptosis of spinal cord neurons.

Cellulose-Pectin Spatial Contacts Are Inherent to Never-Dried Arabidopsis Primary Cell Walls: Evidence from Solid-State Nuclear Magnetic Resonance.

The structural role of pectins in plant primary cell walls is not yet well understood because of the complex and disordered nature of the cell wall polymers. We recently introduced multidimensional solid-state nuclear magnetic resonance spectroscopy to characterize the spatial proximities of wall polysaccharides. The data showed extensive cross peaks between pectins and cellulose in the primary wall of Arabidopsis (Arabidopsis thaliana), indicating subnanometer contacts between the two polysaccharides. This result was unexpected because stable pectin-cellulose interactions are not predicted by in vitro binding assays and prevailing cell wall models. To investigate whether the spatial contacts that give rise to the cross peaks are artifacts of sample preparation, we now compare never-dried Arabidopsis primary walls with dehydrated and rehydrated samples. One-dimensional (13)C spectra, two-dimensional (13)C-(13)C correlation spectra, water-polysaccharide correlation spectra, and dynamics data all indicate that the structure, mobility, and intermolecular contacts of the polysaccharides are indistinguishable between never-dried and rehydrated walls. Moreover, a partially depectinated cell wall in which 40% of homogalacturonan is extracted retains cellulose-pectin cross peaks, indicating that the cellulose-pectin contacts are not due to molecular crowding. The cross peaks are observed both at -20 °C and at ambient temperature, thus ruling out freezing as a cause of spatial contacts. These results indicate that rhamnogalacturonan I and a portion of homogalacturonan have significant interactions with cellulose microfibrils in the native primary wall. This pectin-cellulose association may be formed during wall biosynthesis and may involve pectin entrapment in or between cellulose microfibrils, which cannot be mimicked by in vitro binding assays.

Water-polysaccharide interactions in the primary cell wall of Arabidopsis thaliana from polarization transfer solid-state NMR.

Polysaccharide-rich plant cell walls are hydrated under functional conditions, but the molecular interactions between water and polysaccharides in the wall have not been investigated. In this work, we employ polarization transfer solid-state NMR techniques to study the hydration of primary-wall polysaccharides of the model plant, Arabidopsis thaliana. By transferring water (1)H polarization to polysaccharides through distance- and mobility-dependent (1)H-(1)H dipolar couplings and detecting it through polysaccharide (13)C signals, we obtain information about water proximity to cellulose, hemicellulose, and pectins as well as water mobility. Both intact and partially extracted cell wall samples are studied. Our results show that water-pectin polarization transfer is much faster than water-cellulose polarization transfer in all samples, but the extent of extraction has a profound impact on the water-polysaccharide spin diffusion. Removal of calcium ions and the consequent extraction of homogalacturonan (HG) significantly slowed down spin diffusion, while further extraction of matrix polysaccharides restored the spin diffusion rate. These trends are observed in cell walls with similar water content, thus they reflect inherent differences in the mobility and spatial distribution of water. Combined with quantitative analysis of the polysaccharide contents, our results indicate that calcium ions and HG gelation increase the amount of bound water, which facilitates spin diffusion, while calcium removal disrupts the gel and gives rise to highly dynamic water, which slows down spin diffusion. The recovery of spin diffusion rates after more extensive extraction is attributed to increased water-exposed surface areas of the polysaccharides. Water-pectin spin diffusion precedes water-cellulose spin diffusion, lending support to the single-network model of plant primary walls in which a substantial fraction of the cellulose surface is surrounded by pectins.

Pectin-cellulose interactions in the Arabidopsis primary cell wall from two-dimensional magic-angle-spinning solid-state nuclear magnetic resonance.

The primary cell wall of higher plants consists of a mixture of polysaccharides whose spatial proximities and interactions with each other are not well understood. We recently obtained the first two-dimensional (2D) and three-dimensional high-resolution magic-angle-spinning (13)C solid-state nuclear magnetic resonance spectra of the uniformly (13)C-labeled primary cell wall of Arabidopsis thaliana, which allowed us to assign the majority of (13)C resonances of the three major classes of polysaccharides: cellulose, hemicellulose, and pectins. In this work, we measured the intensity buildup of (13)C-(13)C cross-peaks in a series of 2D (13)C correlation spectra to obtain semiquantitative information about the spatial proximities between different polysaccharides. Comparison of 2D spectra measured at different spin diffusion mixing times identified intermolecular pectin-cellulose cross-peaks as well as interior cellulose-surface cellulose cross-peaks. The intensity buildup time constants are only modestly longer for cellulose-pectin cross-peaks than for interior cellulose-surface cellulose cross-peaks, indicating that pectins come into direct contact with the cellulose microfibrils. Approximately 25-50% of the cellulose chains exhibit close contact with pectins. The (13)C magnetization of the wall polysaccharides is not fully equilibrated by 1.5 s, indicating that pectins and cellulose are not homogeneously mixed on the molecular level. We also assigned the (13)C signals of cell wall proteins, identifying common residues such as Pro, Hyp, Tyr, and Ala. The chemical shifts indicate significant coil and sheet conformations in these structural proteins. Interestingly, few cross- peaks were observed between the proteins and the polysaccharides. Taken together, these data indicate that the three major types of polysaccharides in the primary wall of Arabidopsis form a single cohesive network, while structural proteins form a relatively separate domain.

Multidimensional solid-state NMR studies of the structure and dynamics of pectic polysaccharides in uniformly 13C-labeled Arabidopsis primary cell walls.

Plant cell wall (CW) polysaccharides are responsible for the mechanical strength and growth of plant cells; however, the high-resolution structure and dynamics of the CW polysaccharides are still poorly understood because of the insoluble nature of these molecules. Here, we use 2D and 3D magic-angle-spinning (MAS) solid-state NMR (SSNMR) to investigate the structural role of pectins in the plant CW. Intact and partially depectinated primary CWs of Arabidopsis thaliana were uniformly labeled with (13)C and their NMR spectra were compared. Recent (13)C resonance assignment of the major polysaccharides in Arabidopsis thaliana CWs allowed us to determine the effects of depectination on the intermolecular packing and dynamics of the remaining wall polysaccharides. 2D and 3D correlation spectra show the suppression of pectin signals, confirming partial pectin removal by chelating agents and sodium carbonate. Importantly, higher cross peaks are observed in 2D and 3D (13)C spectra of the depectinated CW, suggesting higher rigidity and denser packing of the remaining wall polysaccharides compared with the intact CW. (13)C spin-lattice relaxation times and (1)H rotating-frame spin-lattice relaxation times indicate that the polysaccharides are more rigid on both the nanosecond and microsecond timescales in the depectinated CW. Taken together, these results indicate that pectic polysaccharides are highly dynamic and endow the polysaccharide network of the primary CW with mobility and flexibility, which may be important for pectin functions. This study demonstrates the capability of multidimensional SSNMR to determine the intermolecular interactions and dynamic structures of complex plant materials under near-native conditions.

Effect of dietary vitamin C on the growth performance and innate immunity of juvenile cobia (Rachycentron canadum).

This study was conducted to evaluate the effects of dietary vitamin C on growth performance, hematologic parameters and innate immune responses in juvenile cobia, Rachycentron canadum. Seven practical diets were formulated to contain 0.0 (as the basal diet), 13.6, 27.2, 54.4, 96.6, 193.4 and 386.5 mg ascorbic acid equivalent kg(-1) diet. Each diet was fed to triplicate groups of juvenile cobia with initial body weight of 5.5 g in 500-L cylindrical fiberglass tank. The results of 8 weeks feeding trial showed that typical vitamin C-deficient signs such as spinal deformation and body nigrescence were observed in the fish fed the basal diet. Fish fed the basal diet had significantly lower weight gain, specific growth rate (SGR), protein efficiency ratio (PER) and feed efficiency (FE) than those fed the diets supplemented with vitamin C, but no significant differences were observed among diets supplemented with vitamin C. However, survival rate was significantly affected by the dietary vitamin C levels, fish fed the basal diet had lower survival rate than those fed the diets supplemented with vitamin C. The ascorbic acid concentration in liver was correlated positively with the dietary vitamin C levels, however, the thiobarbituric acid reactive substances (TBARS) concentrations in liver was not significantly affected by the dietary vitamin C levels, although, fish fed the basal diet had the highest TBARS values among all treatments. The activities of serum lysozyme, superoxide dismutase (SOD), alkaline phophatase (AKP) and total immunoglobulin (Ig) were significantly influenced by the dietary vitamin C levels, fish fed the basal diet had lower lysozyme, SOD, AKP and total Ig than those fed diets supplemented with vitamin C. The serum glucose and triglyceride concentrations were significantly affected by the dietary vitamin C levels. Fish fed the basal diet had lower red blood cell and hemoglobin values than those fed the vitamin C supplemented diets. The challenge experiment with Vibrio harveyi showed that lower cumulative survival was in fish fed the unsupplemented diet, the cumulative survival were significantly increased with increase of the dietary ascorbic acid levels from 13.6 to 96.6 mg kg(-1), while the cumulative survival reached plateau when dietary ascorbic acid levels increased from 96.6 to 386.5 mg kg(-1). These results indicated that dietary vitamin C did significantly influence on growth performance and immune response of juvenile cobia.

Copper in medicine: homeostasis, chelation therapy and antitumor drug design.

As one of the most important essential transition metals, copper is involved in a variety of biological processes such as embryo development, connective tissue formation, temperature control and nerve cell function. It is also related to severe diseases such as Wilson's and Menkes diseases and some neurological disorders. Novel components of copper homeostasis include copper-transporting P-type ATPases, Menkes and Wilson proteins, and copper chaperones in humans have been identified and characterized at the molecular level. These findings have paved the way towards better understanding of the role of copper deficiency or copper toxicity in physiological and pathological conditions. Therefore, organic compounds that can interfere with copper homeostasis may find therapeutic application in copper-dependent diseases. The antitumor activity of copper complexes was reported several decades ago, and many new complexes have demonstrated great antitumor potential. Copper complexes may have relatively lower side effects than platinum-based drugs, and are suggested to be able to overcome inherited or acquired resistance of cisplatin. In this overview, the most recent advances in copper homeostasis, copper-related chelation therapy and design of copper-based antitumor complexes will be summarized.