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Aquatic agriculture in heavy-metal-polluted coastal areas faces major problems due to heavy metal transfer into aquatic organisms, leading to various unexpected changes in nutrition and primary and/or secondary metabolism. In the present study, the dual role of heavy metal copper (Cu) played in the metabolism of photosynthetic organism, the edible seaweed Sargassum fusiforme, was evaluated by characterization of biochemical and metabolic responses using both 1H NMR and GC-MS techniques under acute (47 µM, 1 day) and chronic stress (8 µM, 7 days). Consequently, photosynthesis may be seriously inhibited by acute Cu exposure, resulting in decreasing levels of carbohydrates, e.g., mannitol, the main products of photosynthesis. Ascorbate may play important roles in the antioxidant system, whose content was much more seriously decreased under acute than that under chronic Cu stress. Overall, these results showed differential toxicological responses on metabolite profiles of S. fusiforme subjected to acute and chronic Cu exposures that allowed assessment of impact of Cu on marine organisms. [ABSTRACT FROM AUTHOR]

A fundamental investigation of the biosorption of Cd2+ from aqueous solution by the edible seaweed Sargassum fusiforme was performed under batch conditions. The influences of experimental parameters, such as the initial pH, sorption time, temperature, and initial Cd2+ concentration, on Cd2+ uptake by S. fusiforme were evaluated. The results indicated that the biosorption of Cd2+ depended on the initial Cd2+ concentration, as well as the pH. The uptake of Cd2+ could be described by the Langmuir isotherm model, and both the Langmuir biosorption equilibrium constant and the maximum biosorption capacity of the monolayer decreased with increasing temperature, thereby confirming the exothermic character of the sorption process. The biosorption kinetics follows the pseudo-second-order kinetic model, and intraparticle diffusion is the sole rate-limiting step for the entire biosorption period. These fundamental equilibrium and kinetic results can support further studies to the removal of cadmium from S. fusiforme harvested from cadmium-polluted waters. [ABSTRACT FROM AUTHOR]

Background: Enterovirus 71 (EV71) has been the main causative agent of hand, foot, and mouth disease (HFMD) outbreaks in recent years. A significant increase in the number of HFMD cases in China over the last 3 y has made the public prevention and therapy of this disease a critical issue. Methods: A total of 3208 HFMD patients in Shanghai during the period 2009 to 2010 were analyzed; 437 clinical specimens were collected for the determination of causative pathogens. Eight of the isolated EV71 strains were sequenced and phylogenetically analyzed. Results: The widespread outbreak of HFMD in Shanghai was caused predominantly by EV71 (86.5%), and in part by coxsackievirus A16 (CA16) (6.9%). The high incidence of mixed infections with EV71 and CA16 (17.6% of the total CA16-infected cases) has never before been observed in China. Most HFMD patients (76.9%) were aged 1-4 y. Boys showed a higher HFMD prevalence rate (65.3%) than girls (34.7%). Phylogenetic analysis on the basis of the VP1 gene and the complete genome sequences revealed that the EV71 strains that circulated in Shanghai belonged to the C4 subgenotype. Conclusions: EV71 subgenotype C4 was the major causative agent of the HFMD outbreak in Shanghai. A high incidence of mixed infections with EV71 and CA16 was also observed. [ABSTRACT FROM AUTHOR]

Nitrate reductase activity (NRA) in different plant organs and leaves in different positions of Camptotheca acuminata seedlings was determined by an In vivo assay, the diurnal variation rhythm of NRA in leaves of different positions was observed, and the correlations between leaf NRA, leaf area and lamina mass per unit area (LMA) were also examined. The results showed that NRA in the leaf was significantly highest, compared with that in other organs such as roots, stems and leaves. In this experiment, the 10 leaves were selected from the apex to the base of the seedlings in order. The different NRA occurred obviously in leaves of different positions of C. acuminata seedlings from the apex to the base, and NRA was higher in the 4th–6th leaves. The diurnal change rhythm of leaf NRA showed a one peak curve, and maximum NRA value appeared at about midday (at 12∶30 or so). No obvious correlations between NRA and leaf area or lamina mass per unit area were observed. This study offered scientific foundation for the further research on nitrogen metabolism of C. acuminata. [ABSTRACT FROM AUTHOR]

To lower down the toxicity of camptothecin (CPT), microcapsules loaded with CPT were prepared by using a novel coating technology based on the layer-by-layer (LbL) deposition of oppositely charged chitosan and alginate polyelectrolytes with good biocompatibility onto microcrystal templates. Experimental results show that the microcapsules fabricated by this method have visible core-shell structure observed by confocal laser scanning microscopy ( CLSM), the dispersibility of CPT in water is enhanced, and the release rate can be controlled. The release rate of CPT decreases as the increasing wall thickness ( the number of polyelectrolyte layers deposited onto the microcrystal cores). These microcapsules can reduce the side effects induced by CPT and possess great potential for future application. [ABSTRACT FROM AUTHOR]

A fundamental investigation of the biosorption of Cd2+ from aqueous solution by the edible seaweed Sargassum fusiforme was performed under batch conditions. The influences of experimental parameters, such as the initial pH, sorption time, temperature, and initial Cd2+ concentration, on Cd2+ uptake by S. fusiforme were evaluated. The results indicated that the biosorption of Cd2+ depended on the initial Cd2+ concentration, as well as the pH. The uptake of Cd2+ could be described by the Langmuir isotherm model, and both the Langmuir biosorption equilibrium constant and the maximum biosorption capacity of the monolayer decreased with increasing temperature, thereby confirming the exothermic character of the sorption process. The biosorption kinetics follows the pseudo-second-order kinetic model, and intraparticle diffusion is the sole rate-limiting step for the entire biosorption period. These fundamental equilibrium and kinetic results can support further studies to the removal of cadmium from S. fusiforme harvested from cadmium-polluted waters. [ABSTRACT FROM AUTHOR]

Objective: To study the clinical and molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) infection in children., Method: A total of 37 MRSA strains were isolated from hospitalized patients in Children's Hospital of Fudan University from March 2009 to November 2011. The clinical characteristics were investigated by a cohort study. Furthermore, the mecA, Panton-Valentine leucocidin (PVL) genes were detected by polymerase chain reaction (PCR), and the genotypes of SCCmec were determined by multiplex PCR., Result: (1) Among the 37 MRSA isolates, infections with 21 were acquired from hospital (HA-MRSA), and 16 isolates were acquired from community (CA-MRSA). (2) In the study, MRSA frequently caused respiratory tract infection, and most of the strains were isolated from intensive care unit (ICU). (3) CA-MRSA was most frequently associated with skin and soft tissue infections (SSTI), suppurative tonsillitis, even pneumonia and septicemia. HA-MRSA infection was more aggressive, most frequently associated with pneumonia, septicemia, and central nervous system (CNS) infections, such as meningitis. In children with fever caused by HA-MRSA or CA-MRSA infection, HA-MRSA showed a longer duration of fever, for 10.5 days. C-reactive protein (CRP) level caused by HA-MRSA (63.00 mg/L) was higher than CA-MRSA (9.50 mg/L) , and there were statistically significant differences between the groups (t = 2.5670, P < 0.05). However, there were no statistically significant differences between the groups in white blood cell count (WBC) or procalcitonin (PCT) level. (4) Among 37 MRSA isolates, the whole isolates were mecA gene positive (100%). SCCmec genotyping results showed that the most frequent SCCmec types were type III, 17 isolates, the others including type IV 8 isolates, type II1 isolates, nontypable 11 isolates, type I and type V were not found in this group. Therein, among 21 HA-MRSA isolates, SCCmec III was the most common, 15 isolates, type IV 1 isolates, nontypable 5 isolates; among 16 CA-MRSA isolates, SCCmec type IV was the most common, 7 isolates, type III 2 isolates, type II 1 isolate, nontypable 6 isolates. (5) Among the 37 MRSA isolates, 28 were PVL gene positive; and among 21 HA-MRSA isolates, 17 were PVL gene positive; Among 16 CA-MRSA isolates, 11 were PVL gene positive; There were no statistically significant differences between the groups (χ(2) = 0.735, P > 0.05) ., Conclusion: Compared with CA-MRSA, HA-MRSA infection was more aggressive, and induced higher C reactive protein; the dominant epidemic strains of CA-MRSA was SCCmec type IV, and HA-MRSA was SCCmec type III; the positive rate of PVL gene was high.

Objective: To retrospectively analyzed the clinical features and epidemiology of children with severe hand-foot-and-mouth disease during 2009 and 2010 in Shanghai to investigate some risk factors with fatal cases., Method: All the clinical records and laboratory results of serious patients were collected. A retrospective study was performed., Result: A total of 748 serious patients were enrolled into this study, and the ratio of male to female was about 1.7:1; 724 patients were categorized into stage 2 with 254 patients in 2009 and 470 in 2010; 24 patients were categorized into stage 3 with 17 in 2009 and 7 in 2010. The rate of severity in 2010 (1.5%) was lower than in 2009 (6.3%) (χ2=12.836, P<0.01). Seven patients of stage 3 died, with the fatality 29.2%, which was higher than in stage 2 (P<0.01). The children aged between 3 months 10 days to 12 years 9 months with onset median age of 25 months. Among them, 77.1% patients aged between 1 and 4 years which also accounted for 79.2% of the fatal cases (19/24). But there was no significant difference between the age and the severity (χ2=0.804, P>0.05). Fever (100%), vomiting (57.0%) and myoclonus jerk (62.3%) were the most frequent symptoms occurred in those serious cases. The average period of fever in children of stage 2 and 3 was (4.10±1.40) d and (5.05±1.05) d, respectively, which indicated significant difference between the two groups (t=3.173, P<0.05). The average values of white-blood-cell counts and blood glucose in fatal patients were (14.8±6.25)×10(9)/L and (8.63±3.51) mmol/L. They were higher when compared to those in stage 2 with the white-blood-cell counts of (11.8±4.23)×10(9)/L and blood glucose of (5.51±2.14) mmol/L (P<0.05). But there was no significant difference in C-reactive protein or cerebrospinal fluid white-blood-cell counts; A total of 182 patients were enrolled for MRI study during the acute stage with 37 (37/182, 20.3%) presented abnormal findings. Among them, most frequent findings were hyperintense lesions seen in brain stem (11 cases). A stage 3 case who died presented brain edema on MRI examination., Conclusion: The epidemic of HFMD has some correlation with the area, season, health condition of the family and gender of the children. Children under 4 years of age especially those who lived in rural areas were susceptible to the HFMD. Frequent vomiting or myoclonus jerk may indicate the central nervous system involvement. But persistent high fever may indicate tendency to deteriorate. Some laboratory examinations can help find the fatal cases at an early time.

In this study we initiated a proteomic investigation of the maize thylakoid membrane by using a shotgun proteomic approach based on LC-MS(E). A total of 34 maize thylakoid membrane proteins were identified, the majority of which are primarily involved in photosynthesis, including the light-reaction and carbon assimilation. It is noteworthy that all of the core subunits of the Photosystem II were identified in our search. Proteins involved in other processes, such as iron storage, were also detected in our study. The quantity of each identified protein was also determined. Of interest, we discovered that the amount of the three ATP synthase subunits were not equivalent, suggesting that these proteins perform other functions in addition to ATP synthesis. To our knowledge this is the first extensive proteomic investigation of the maize thylakoid membrane, and will likely enable further study of maize photosynthesis and chloroplast development.

In the title mol-ecule, C(34)H(53)BrO(4), all the cyclo-hexane rings adopt chair conformations, while the cyclo-pentane ring adopts an envelope conformation. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into corrugated sheets parallel to the ab plane.

Using cDNAs prepared from the leaves and stems of Polygonum sibiricum Laxm. treated with NaHCO3 stress for 48 h as testers and cDNAs from unstressed P. sibiricum leaves and stems as drivers library, suppression subtractive hybridization (SSH) was employed to construct a cDNA subtracted library, which contained 2 282 valid sequences including 598 ESTs in the stems forward SSH library and 490 ESTs in the stem reverse SSH library, 627 ESTs in the leaf forward SSH library and 567 in the leaf reverse SSH library. According to the functional catalogue of MIPs and the comparison of the reverse and forward SSH libraries of the stem and leaf, the responses to NaHCO3 stress were different between leaf and stem, except for the same trend in cell rescue defense and transport facilitation. The trend in the metabolism, energy, photosynthesis, protein synthesis, transcription, and signal transduction was opposite. RT-PCR analysis demonstrated that the expression of 12 putative stress related genes in the NaHCO3-treated leaves and stems was different from that in the untreated leaves and stems. This indicated that different mechanisms might be responsible for reactions of leaf and stem in P. sibiricum. The results from this study are useful in understanding the molecular mechanism of saline-alkali tolerance in P. sibiricum.

Gene PsPIP1 (GenBank accession No. EU626398) containing a complete ORF was obtained using rapid amplification of cDNA ends (RACE) from the cDNA library of Polygonum sibiricum Laxm. leaves. The length of cDNA was 1 004 bp, which encoded a peptide of 285 amino acid residues. Based on other kinds of plant aquaporin amino acid sequences, the phylogenetic evolution, and tertiary structure of protein comparison, this gene was classified into aquaporin subfamily. Expression analysis by Real-time PCR showed that PsPIP1 gene was expressed in leaves, stems, and underground stems. The expression level of PsPIP1 gene was higher in leaves than in underground stems and was the lowest in stems. The expression pattern of PsPIP1 gene induced by NaHCO3 stress and de-stressing also varied remarkably.

Cysteine synthase is a key enzyme for restricting plant cysteine synthesis. Cysteine synthase gene, designated PcCSase1 (GenBank accession no. EU597481), was successfully isolated from Polygonum sibiricum Laxm. by RACE technique. This gene was 1 260 bp in full-length and encoded a peptide of 382 amino acids. Based on bioinformatic analysis, PcCSase1 is a cytoplasm cysteine synthesis and contains a 16 amino-terminal (N-terminal) signal peptide, which led the PcCSase1 to go to the cytoplasm. The results obtained through homologous sequence analysis indicated that PcCSase1 mature protein was highly conserved in plants, which shared approximate 90% in the amino acid sequence. Expression analysis by RT-PCR showed that PcCSase1 gene was expressed in leaf, stem and root with the largest expression in leaf. Under 3% NaHCO3 stress, the largest expression of PcCSase1 gene was detected in leaf, stem and root at the second day following stress. PcCSase1 gene was inserted into pYES2 and transformed into yeast cells (Saccharomyces cerevisiae). The contents of the glutathione in the recombinant yeast and the cysteine in the medium were increased. INVSc1-pYES2-PcCSase1 was more tolerant to salt treatment than INVSc1-pYES2 and the former survival rate was higher than that of the later under the stress of 10% NaHCO3 and 5 mol/L NaCl. These results proved that PcCSase1 gene may confer high salt-tolerance.

Objective: To investigate the effects of nitrogen forms on the camptothecin (CPT) content, tryptophan synthase (TSB) and tryptophan decarboxylase (TDC) activities in Camptotheca acuminata seedlings., Method: The seedlings of C. acuminata with 6 pairs of leaves were subjected to 5 different NH4(+) -N/NO3(-) -N ratio (0 : 100, 75 : 25, 50 : 50, 25 : 75, 100 : 0) treatments by sand culture in a greenhouse. The CPT content, TSB activity in the young leaves and TDC in the stem barks of the seedlings were determined by HPLC on the 15th, 30th, 45th, 60th and 75th day, respectively., Result: The obvious relationship between CPT content and nitrogen forms was observed. When NH4(+) - N /NO3(-) -N ratio was 25 : 75, CPT accumulation in young leaves displayed the best advantages (the highest value is 5.69 per thousand) and increased in the early 30 days of treatment and then declined. There was no obvious relationship between TSB activity in the young leaves and nitrogen forms. TDC activity in the stem bark was the highest when NH4(+) -N /NO3(-) -N ratio was 25 : 75, and the change of TDC activity paralleled to CPT content in the young leaves., Conclusion: A short-term treatment that NH4(+) -N /NO3(-) -N ratio was 25:75 may gain high CPT content in the young leaves through enhancing the TDC activity in the stem bark of C. acuminata seedlings.

Objective: To investigate the effects of nitrogen concentration on the camptothecin (CPT) content in Camptotheca acuminata seedlings:, Method: The seedlings of C. acuminata with 6 pair of leaves were subjected to five nitrogen concentrations treatments by sand culture in a greenhouse. The CPT content in the seedlings was determined by HPLC on the 20th, 35th, 50th, 65th and 80th day respectively., Result: The CPT content in the young leaves of C. acuminata seedlings supplied with different nitrogen concentration was significantly higher than that in other organs (P < 0.01), and it showed a single peak curve with the time course, the highest CPT content was observed on the 50th day after treatment. The CPT content in the young leaves obviously declined with increasing nitrogen concentration, and it reached the highest (6.72%) when nitrogen concentration was 4 mmol x L(-1), equal to 1.1 times that of 16 mmol x L(-1) nitrogen., Conclusion: The results demonstrate that proper deficient nitrogen stress can significantly enhance CPT accumulation in young leaves of C. acuminata seedlings.