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Paddy rice-upland crop rotation system is a major cropping system in China, and practiced widely along the Yangtze River basin. A unique feature of this system is the annual conversion of soil from aerobic to anaerobic and then back to aerobic condition, which can result in the changes of soil physical, chemical, and biological prosperities among seasons, making a special agroecosystem. The major challenges faced by this system include declining or stagnating productivity, increasing shortage of irrigation water, improper management of nutrients, low efficiency of resource utilization, and environmental pollution. Based on an overview of the characteristics and problems of paddy rice-upland crop rotation system, this paper put forward a strategy of practicing integrated nutrient management to solve the contradictions between nutrient input, crop production and environmental risk. The key points of this strategy included nutrient management from the whole rotation system perspective, integrated use of nutrients from various sources (chemical fertilizers, organic fertilizers, and nutrients from the environment), synchronization of nutrient supply and crop nutrient demand, application of different management technologies based on the characteristics of different nutrient resources, and integration of nutrient management with other cropping system technologies like water saving and high-yielding cultivation, etc.

Objective: To investigate the influence of butt joint connection and platform switching design of implant-abutment connection on the stress distribution in peri-implant bone., Methods: Three-dimensional finite element models of implant-supported mandibular first molar with different implant-abutment connections were computed by COSMOSM 2.85. Traditional butt joint connection was used in model A and platform switching design in model B. Loading conditions were a vertical load of 200 N and inclined load of the same magnitude at 45 degrees to the vertical axis of the implant. Stress distribution in peri-implant bone and von Mises stresses at the same point of buccal and lingual implant-bone interfaces in two models were compared., Results: Stresses concentrated in peri-implant cortical bone at the neck of implants on the buccal and lingual sides; maximum von Mises stresses under inclined load were higher than those under vertical load. Maximum von Mises stress in bone was 11.61 MPa in model A and 7.15 MPa in model B under vertical load, and 22.07 MPa in model A and 11.87 MPa in model B under inclined load respectively. Von Mises stresses decreased as the distance from implant-abutment junction increased and the most obvious change occurred at the interface between cortical bone and spongy bone. Von Mises stresses at the same points of buccal and lingual implant-bone interfaces in model A were higher than those in model B., Conclusions: Compared with butt joint connection, platform switching design improved the stress distribution and decreased the maximum stresses in peri-implant bone around implant cervix.

Semi-dwarfism is an important agronomic trait in rice breeding programmes. sd-1, termed the 'Green Revolution gene', confers semi-dwarf stature, increases harvest index, improves lodging resistance, and is associated with increased responsiveness to nitrogen fertilizer. It has contributed substantially to the significant increase in rice production. In this paper, a novel semi-dwarf mutant in rice is reported. Genetic analysis revealed that only a single dominant gene locus non-allelic to sd-1, temporarily designated Sdt97, is involved in the control of semi-dwarfism of the mutant. The semi-dwarfism of the mutant could be partly restored to the tall wild-type by application of exogenous GA3, suggesting that the mutant gene Sdt97 may be involved in the gibberellin (GA) synthesis pathway and not the GA response pathway in rice. A residual heterozygous line (RHL) population derived from a recombinant inbred line (RIL) was developed. Simple sequence repeat (SSR) and bulked segregation analysis (BSA) combined with recessive class analysis (RCA) techniques were used to map Sdt97 to the long arm of chromosome 6 at the interval between two STS markers, N6 and TX5, with a genetic distance of 0.2 cM and 0.8 cM, respectively. A contig map was constructed based on the reference sequence aligned by the Sdt97 linked markers. The physical map of the Sdt97 locus was defined to a 118 kb interval, and 19 candidate genes were detected in the target region. This is the first time that a dominant semi-dwarf gene has been reported in rice. Cloning and functional analysis of gene Sdt97 will help us to learn more about molecular mechanism of rice semi-dwarfism.

Objective: To investigate the upper airway structure of sleep-disordered breathing children., Methods: Seventy three children with obstructive sleep apnea hypopnea syndrome (OSAHS), 53 children with primary snoring (PS) and 40 control subjects underwent pharyngeal magnetic resonance imaging (MRI). Upper airway structure images were analyzed and measured., Results: The cross-section area of the nasopharyngeal and palatopharyngeal airway in subjects with OSAHS and PS are smaller (P < 0.01) than that of the control group. The cross section area of OSAHS patients are smaller than that of PS subjects (P < 0.01). The above parameter of oropharyngeal airway in OSAHS patients is smaller than that of control group (P < 0.01), but no statistic difference compared with that of PS subjects. The cross-section area and length of the adenoid in OSAHS group are bigger and longer than that of PS group (P < 0.01) and bilateral tonsils are larger (P < 0.01); in OSAHS patients the cross-section area of the soft palate is larger and the length of the soft palate is longer (P < 0.01) than that of PS group, while this parameter of PS group is similar to that of the control group. And the maximum width of the soft palate, the cross-section area of bilateral fat pad, bilateral pterygoid and tongue are similar among OSAHS, PS and the control group. The skeletal measurement: the length of H-C2C3 in subjects with OSAHS is longer (P < 0.01); The angle(alpha) in OSAHS patients is smaller (P < 0.01) than that of other 2 groups. The angle (beta), the cross-section area of the mandible, the spine-clivus oblique, the length of the hard palate and the distance of the mandible are similar among the three groups., Conclusions: In children with OSAHS or PS, the upper airway is restricted by both the adenoid and tonsils; however, the soft palate is also larger in OSAHS, adding further restriction. Otherwise, downward movement of the hyoid bone and decreasing of the angle (alpha) in OSAHS influence laryngopharynx airway. MRI is of clinical significance for evaluating OSAHS children's upper airway.

In type 1 diabetes, T cell-mediated death of pancreatic beta cells produces insulin deficiency. However, what attracts or restricts broadly autoreactive lymphocyte pools to the pancreas remains unclear. We report that TRPV1(+) pancreatic sensory neurons control islet inflammation and insulin resistance. Eliminating these neurons in diabetes-prone NOD mice prevents insulitis and diabetes, despite systemic persistence of pathogenic T cell pools. Insulin resistance and beta cell stress of prediabetic NOD mice are prevented when TRPV1(+) neurons are eliminated. TRPV1(NOD), localized to the Idd4.1 diabetes-risk locus, is a hypofunctional mutant, mediating depressed neurogenic inflammation. Delivering the neuropeptide substance P by intra-arterial injection into the NOD pancreas reverses abnormal insulin resistance, insulitis, and diabetes for weeks. Concordantly, insulin sensitivity is enhanced in trpv1(-/-) mice, whereas insulitis/diabetes-resistant NODxB6Idd4-congenic mice, carrying wild-type TRPV1, show restored TRPV1 function and insulin sensitivity. Our data uncover a fundamental role for insulin-responsive TRPV1(+) sensory neurons in beta cell function and diabetes pathoetiology.

Objective: To investigate the relationship between the blood flow of the exceedingly expanded skin and the viability of the flap., Methods: The piglets were set up as the animal model. They were divided into 7 groups according to different injection volume of the tissue expander, i. e. injection to 1/2 content, 3/4 content, full content, 50% over content, 100% over content, sham-operation control and normal control. At different stages of expansion, the blood flow and the amplitude of the expanded skin were examined by laser Doppler. The survival length of the expanded flap was measured. Furthermore, statistical analysis was performed., Results: As the expansion volume increasing, the blood flow and the amplitude of the expanded skin increased, the survival length of the expanded flap increased also. In the meantime, the amplitude instability and vessel permeability increased. When the injection volume exceeded to 100%, the blood flow and the survival length of the expanded flap decreased., Conclusions: In soft tissue and skin expansion, increasing injection volume could increase the survival length of the expanded flap, while over-expansion to 100% content may cause blood flow disturbance.

Objective: To detective the relationship between cyclooxygenase-2 (COX-2) and angiogenesis in oral squamous cell carcinoma (OSCC) and its clinical significance through observing the expression of COX-2 and determining microvessel density (MVD) in OSCC., Methods: PV-9000 immunohistochemistry was used to determine the expression of COX-2 and CD34, which was used to determine MVD, in 76 OSCC tissues and 12 normal oral mucosa tissues., Results: Overexpression of COX-2 was detected in OSCC, and was more intense compared with normal epithelium (P < 0.001). The high expression of COX-2 in OSCC was related to neck lymphnode metastasis, tumor size, TNM stage and histological grade (P <0.05). The MVD value in COX-2-positive group was much higher than that in COX-2-negative group (P < 0.01) and that in normal oral mucosa tissues (P < 0.01)., Conclusion: The high expression of COX-2 in OSCC was significantly associated with MVD, neck lymphnode metastasis, tumor size, TNM stage and histological grade. COX-2 might be one of the important factors in the angiogenesis of OSCC.

Local administration of amitriptyline into the rat hindpaw produces peripheral antinociception; this is reduced by adenosine receptor antagonists and appears to involve endogenous adenosine. The present study used peripheral microdialysis: (a) to determine whether amitriptyline could enhance extracellular tissue levels of endogenous adenosine in the rat hindpaw and (b) to examine mechanisms by which such an increase could occur. Local injection of amitriptyline into the plantar hindpaw, at doses that produce peripheral antinociception (100-300 nmol), produced an increase in local extracellular levels of adenosine. When injected in combination with formalin, which also enhances such levels of adenosine, an additive increase was observed. This adenosine originated partly as nucleotide, as inhibition of ecto-5'-nucleotidase reduced the amount of adenosine detected in the probe following administration of amitriptyline. When administered in combination with exogenous adenosine, amitriptyline augmented recovery of adenosine in the probe. Pretreatment of rats with capsaicin augmented the ability of amitriptyline to increase adenosine levels detected in the dialysis probe; it also enhanced tissue recovery of exogenously administered adenosine. In uptake studies using cultured rat C6 glioma cells, amitriptyline inhibited adenosine uptake by an adenosine transporter (IC50 0.37 +/- 0.12 mM). In enzyme assays, amitriptyline had no effect on adenosine kinase or adenosine deaminase activity. These results demonstrate that amitriptyline: (a) enhances extracellular tissue levels of adenosine in the rat hindpaw following local administration in vivo and (b) inhibits adenosine uptake but has no effect on metabolism in vitro. Therefore, increased extracellular adenosine levels in vivo appear to result partially from extracellular conversion of nucleotide and partially from inhibition of uptake.

Purines, such as adenosine and ATP, are endogenous ligands involved in modulating pain transmission and pain hypersensitivity by acting on P1 and P2 purinoceptors, respectively, at sites both in peripheral tissues and in the central nervous system. For P1 (adenosine) receptors, clinical studies in humans, as well as experimental animal studies, have demonstrated that activation of the A1 subtype reduces both inflammatory and neuropathic types of chronic pain. For P2 receptors, there is a growing body of evidence indicating that multiple receptor subtypes are differentially involved in pain processing. The most well-known of the P2 receptors is the P2X3 subtype, which is found in primary sensory neurons. Inhibition of P2X3 receptors is effective in reducing pain behaviors in animal models of chronic inflammatory and neuropathic pain. Recently, the P2X, subtype has been implicated in nerve-injury-induced pain hypersensitivity. There is also emerging evidence for roles for P2Y, and P2Y2 receptors, subtypes of G protein-coupled P2 receptors, in pain hypersensitivity. Thus, multiple subtypes of purinoceptors are potential molecular targets for development of new pharmacological agents for the treatment of pain.

Objective: To study the correlation between the expansion with different volume and the contents of the b-FGF and EGF in the expanded skin., Methods: The piglets were used in the experiment,which were divided into 7 groups including the sham, the blank control,the experimental groups with inflation of 1/2 volume, 3/4 volume, full volume, 150% volume and 200% volume. When expansion was complete, b-FGF was measured using enzyme coagulate method. EGF was measured by radioimmunoassay. The data were analyzed statistically., Results: The contents of b-FGF and EGF in the expanded skin was significantly higher than normal skin (P < 0.05). The difference in contents of b-FGF and EGF between the over-expanded skin and normal skin was more significant (P < 0.01)., Conclusion: Expansion can lead to the increase of b-FGF and EGF contents in the expanded skin.The biological effects may be relative to epidermal hyperplasia and angiogenesis of the expanded skin.

In this study, fatty-acid content and patterns were analyzed in order to distinguish Nostoc flagelliforme, an edible terrestrial cyanobacterium, from other Nostoc species and representatives typical of its close neighbors (genera Anabaena, Microcystis, and Synechococcus). According to the Kenyon-Murata classification system, all the Nostoc species were assigned to Group II due to the presence of C18:2n3 and C18:3n3, and the absence of C18:3n6. Hierarchical cluster analysis was also employed to separate N. flagelliforme and other Nostoc species or strains. A dendrogram calculation of all fatty-acid components manifested phenetic characteristics, showing that the degree of relatedness of two strains of N. flagelliforme aggregated them within a small subgroup. Another dendrogram, calculated from seven comprehensive parameters (including ratios of different fatty-acid categories, degree of fatty-acid unsaturation, etc.), also clearly delimited the minute difference in fatty-acid profiles between the tested organisms. Our results suggest that profiling fatty acids could be a useful approach in the taxonomic or phylogenetic study of the genus Nostoc and might serve as a valuable supplement to the current morphology-based classification system.

In the central nervous system (CNS), adenosine is an important neuromodulator and regulates neuronal and non-neuronal cellular function (e.g. microglia) by actions on extracellular adenosine A(1), A(2A), A(2B) and A(3) receptors. Extracellular levels of adenosine are regulated by synthesis, metabolism, release and uptake of adenosine. Adenosine also regulates pain transmission in the spinal cord and in the periphery, and a number of agents can alter the extracellular availability of adenosine and subsequently modulate pain transmission, particularly by activation of adenosine A(1) receptors. The use of capsaicin (which activates receptors selectively expressed on C-fibre afferent neurons and produces neurotoxic actions in certain paradigms) allows for an interpretation of C-fibre involvement in such processes. In the spinal cord, adenosine availability/release is enhanced by depolarization (K(+), capsaicin, substance P, N-methyl-D-aspartate (NMDA)), by inhibition of metabolism or uptake (inhibitors of adenosine kinase (AK), adenosine deaminase (AD), equilibrative transporters), and by receptor-operated mechanisms (opioids, 5-hydroxytryptamine (5-HT), noradrenaline (NA)). Some of these agents release adenosine via an equilibrative transporter indicating production of adenosine inside the cell (K(+), morphine), while others release nucleotide which is converted extracellularly to adenosine by ecto-5'-nucleotidase (capsaicin, 5-HT). Release can be capsaicin-sensitive, Ca(2+)-dependent and involve G-proteins, and this suggests that within C-fibres, Ca(2+)-dependent intracellular processes regulate production and release of adenosine. In the periphery, adenosine is released from both neuronal and non-neuronal sources. Neuronal release from capsaicin-sensitive afferents is induced by glutamate and by neurogenic inflammation (capsaicin, low concentration of formalin), while that from sympathetic postganglionic neurons (probably as adenosine 5'-triphosphate (ATP) with NA) occurs following more generalized inflammation. Such release is modified differentially by inhibitors of AK and AD. Following nerve injury, there is an alteration in capsaicin-sensitive adenosine release, as spinal release now is less responsive to opioids, while peripheral release is less responsive to inhibitors of metabolism. Following inflammation, adenosine is released from a variety of cell types in addition to neurons (e.g. endothelial cells, neutrophils, mast cells, fibroblasts). ATP is released both spinally and peripherally following inflammation or injury, and may be converted to adenosine by ecto-5'-nucleotidase contributing an additional source of adenosine. Release of adenosine from both spinal and peripheral compartments has inhibitory effects on pain transmission, as methylxanthine adenosine receptor antagonists reduce analgesia produced by agents which augment extracellular levels of adenosine spinally (morphine, 5-HT, substance P, AK inhibitors) and peripherally (AK inhibitors, AD inhibitors). Increases in extracellular adenosine availability also may contribute to antiinflammatory effects of certain agents (methotrexate, sulfasalazine, salicylates, AK inhibitors), and this could have secondary effects on pain signalling in chronic inflammation. The purpose of the present review is to consider: (a). the factors that regulate the extracellular availability of adenosine in the spinal cord and at peripheral sites; and (b). the extent to which this adenosine affects pain signalling in these two distinct compartments.

The trophic transfer of metals along the food chain has been recognized as an important issue in the study of water quality in recent years. Feeding experiments were conducted to examine the assimilation of three metals (Cd, Cr and Zn) by the zebrafish Danio reiro feeding on the freshwater zooplankton Daphnia magna. The zooplankton were exposed to radiotracers from both the aqueous and dietary phases for different duration, and then pulse-fed to the zebrafish for measurements of metal assimilation efficiency (AE). The calculated AEs were 3-8% for Cd, 2-39% for Cr, and 17-36% for Zn in the zebrafish. For Cd and Zn, there was no statistically significant difference between the two different radiolabeling routes (aqueous and dietary exposure). For Cr, the AEs were higher when it was accumulated by D. magna from the dietary source than when it was accumulated from the aqueous phase. The gut passage time (GPT) was 6-10 h for all metals, with less variation for Zn among the different treatments. There was no obvious relationship between metal GPT and metal AE, presumably due to the narrow range of variation of metal gut passage. About 5-36%, 20-31%, and 8-30% of the total Cd, Cr and Zn was found in the soft tissue of D. magna after the radiolabeling. A much higher fraction of Cd and Zn was found in the soft tissue of D. magna when the metals were accumulated from the dietary phase. No significant relationship between the metal AE and the metal distribution in the soft tissue of D. magna was however documented in this study. Our results demonstrated that there was major difference in metal AE in freshwater fish among different metals. Metal localization in prey organisms and GPT appear to have little influence on metal assimilation by the zebrafish.

Objective: To study the expression of matrix metalloproteinase-9 (MMP-9) in ectopic and eutopic endometrium from women with endometriosis, thereby to determine the role of matrix metalloproteinases in the pathogenesis of endometriosis., Methods: Both ectopic and eutopic endometrium tissue specimens were obtained from 30 women with endometriosis, and gelatinase activity in the specimens was detected by zymography and quantitated by Gel Documentation Analysis System., Results: MMP-9 was detected in both eutopic and ectopic endometrium, but the latter contained higher levels of MMP-9 than the former did, and as the endometriosis worsened, MMP-9 expression tended to increase further., Conclusion: Endometriotic tissue possesses higher level of gelatinase activity than eutopic endometrium from patients with endometriosis does, and MMP-9 might be of importance for the implantation and invasive growth of endometriotic tissue that may lead to endometriosis.

Glutamate receptors have been identified on the peripheral terminals of both primary sensory afferents and sympathetic post-ganglionic neurons, and activation of these receptors produces peripheral sensitization and enhances nociception. Adenosine is an endogenous agent that has a regulatory effect on pain. In brain and spinal cord, adenosine release can be promoted by excitatory amino acids. In the present study, we used in vivo microdialysis to determine whether glutamate also can release adenosine in peripheral tissues. Rats were anesthetized with pentobarbital and microdialysis probes were implanted into the subcutaneous tissue of the plantar aspect of the rat hind paw. Subcutaneous injection of glutamate (50 microL, 0.3-100 micromol) evoked a short-lasting adenosine release immediately following drug injection. Co-administration of either the N-methyl-D-aspartate (NMDA) receptor antagonist, dizocipine maleate (MK-801, 1 nmol) or the non-NMDA receptor antagonist, 6-cyano-7-nitroquinoxaline (CNQX, 10 nmol) with glutamate blocked such release, suggesting an involvement of peripheral ionotropic glutamate receptors in this response. Systemic pre-treatment with capsaicin, a neurotoxin selective for unmyelinated sensory afferents, significantly reduced glutamate-evoked peripheral adenosine release, but release was not affected by systemic pre-treatment with 6-hydroxydopamine, a neurotoxin selective for sympathetic nerve efferents. Neither MK-801 nor CNQX blocked 5% formalin-evoked adenosine release, suggesting adenosine release by formalin is not secondary to ionotropic glutamate receptor activation. We conclude that administration of glutamate evokes peripheral adenosine release, and that peripheral ionotropic glutamate receptors on unmyelinated sensory afferents are involved in such release. The released adenosine may provide a negative feedback control on nociception.