香蕉种植密度对蕉园光能利用与产量的影响

本试验研究了福建沿海地区蕉园种植密度与光能利用效率和产量之间的关系。结果表明,适当提高种植密度,可增加香蕉单位空间的光能利用,充分利用地力,改善蕉园生态条件,显著地提高香蕉亩产量。亩植160～180株是沿海地区达到高产稳产的有效措施。     

建立石门台省级自然保护区的论证与规划

论述了建立石门台省级自然保护区的重要性,自然条件及生物资源概况,论证了建立石门台省级自然保护的自然环境条件、社会经济条件和自然资源条件,提出了建立石门台省级自然保护区的规划原则,进行了功能类型规划。最后,对建立石门台省级自然保护区效益进行了评价。     

Eotaxin activates T cells to chemotaxis and adhesion only if induced to express CCR3 by IL-2 together with IL-4

The transmigration and adherence of T lymphocytes through microvascular endothelium are essential events for their recruitment into inflammatory sites. In the present study, we investigated the expression of CC chemokine receptor CCR3 on T lymphocytes and the capacities of the CC chemokine eotaxin to induce chemotaxis and adhesion in T lymphocytes. We have observed a novel phenomenon that IL-2 and IL-4 induce the expression of CCR3 on T lymphocytes. We also report that CC chemokine eotaxin is a potent chemoattractant for IL-2- and IL-4-stimulated T lymphocytes, but not for freshly isolated T lymphocytes. Eotaxin attracts T lymphocytes via CCR3, documented by the fact that anti-CCR3 mAb blocks eotaxin-mediated T lymphocyte chemotaxis. In combination with IL-2 and IL-4, eotaxin enhances the expression of adhesion molecules such as ICAM-1 and several integrins (CD29, CD49a, and CD49b) on T lymphocytes and thus promotes adhesion and aggregation of T lymphocytes. The eotaxin-induced T lymphocyte adhesion could be selectively blocked by a specific cAMP-dependent protein kinase inhibitor, H-89, indicating that eotaxin activates T lymphocytes via a special cAMP-signaling pathway. Our new findings all point toward the fact that eotaxin, in association with the Th1-derived cytokine IL-2 and the Th2-derived cytokine IL-4, is an important T lymphocyte activator, stimulating the directional migration, adhesion, accumulation, and recruitment of T lymphocytes, and paralleled the accumulation of eosinophils and basophils during the process of certain types of inflammation such as allergy.     

Opposing seasonal temperature dependencies of CO2 and CH4 emissions from wetlands

Wetlands are critically important to global climate change because of their role in modulating the release of atmospheric greenhouse gases (GHGs) carbon dioxide (CO₂) and methane (CH₄). Temperature plays a crucial role in wetland GHG emissions, while the general pattern for seasonal temperature dependencies of wetland CO₂ and CH₄ emissions is poorly understood. Here we show opposite seasonal temperature dependencies of CO₂ and CH₄ emissions by using 36,663 daily observations of simultaneous measurements of ecosystem-scale CO₂ and CH₄ emissions in 42 widely distributed wetlands from the FLUXNET-CH₄ database. Specifically, the temperature dependence of CO₂ emissions decreased with increasing monthly mean temperature, but the opposite was true for that of CH₄ emissions. Neglecting seasonal temperature dependencies may overestimate wetland CO₂ and CH₄ emissions compared to the use of a year-based static and consistent temperature dependence parameter when only considering temperature effects. Our findings highlight the importance of incorporating the remarkable seasonality in temperature dependence into process-based biogeochemical models to predict feedbacks of wetland GHG emissions to climate warming.     

15—Mt—PGF2α对CCL4所致大鼠离体肝细胞损伤的保护作用

采用大鼠离体肝细胞原代培养２４ｈ,并利用四氯化碳ＣＣｌ４造成急性肝细胞损伤模型,检定１５－甲基－前列腺素Ｆ２α（１５－Ｍｔ－ＰＧＦ２α）对肝细胞损伤的影响。结果表明：（１）１５－Ｍｔ－ＰＧＦ２α可显著降低中毒肝细胞脂质过氧化物水平,抑制肝细胞脂质过氧化,并降低谷丙转氨酶（ＧＰＴ）和谷草转氨酶（ＧＯＴ）水平,稳定脂质膜。（２）显著促进中毒肝细胞ＲＮＡ和ＤＮＡ的合成。（３）超微结构证实１５－Ｍｔ－ＰＧＦ２α能减轻ＣＣｌ４对肝细胞脂质膜,染色质,线粒体,内质网和核蛋白体的损害。     

阳宗海和滇池中紫色非硫细菌数量和种群结构的比较

在2002年平水期对高原湖泊阳宗海和滇池中的紫色非硫细菌(PNSB)数量和种群结构进行了比较研究。对两湖中的各因子进行t检验,发现各因子和PNSB数量都有极显著差异,富营养化湖泊滇池中的PNSB数量远远多于贫营养化湖泊阳宗海;两湖中PNSB的优势种是红假单胞菌属,也有少数的红螺菌属。两湖种群结构的区别是滇池有红微菌,而阳宗海有大量红细菌。     

Structural Basis for the Dual Recognition of IL-12 and IL-23 by Ustekinumab

Interleukin (IL)-12 and IL-23 are heterodimeric proinflammatory cytokines that share a common p40 subunit, paired with p35 and p19 subunits, respectively. They represent an attractive class of therapeutic targets for the treatment of psoriasis and other immune-mediated diseases. Ustekinumab is a fully human monoclonal antibody (mAb) that binds specifically to IL-12/IL-23p40 and neutralizes human IL-12 and IL-23 bioactivity. The crystal structure of ustekinumab Fab (antigen binding fragment of mAb), in complex with human IL-12, has been determined by X-ray crystallography at 3.0 Å resolution. Ustekinumab Fab binds the D1 domain of the p40 subunit in a 1:1 ratio in the crystal, consistent with a 2 cytokines:1 mAb stoichiometry, as measured by isothermal titration calorimetry. The structure indicates that ustekinumab binds to the same epitope on p40 in both IL-12 and IL-23 with identical interactions. Mutational analyses confirm that several residues identified in the IL-12/IL-23p40 epitope provide important molecular binding interactions with ustekinumab. The electrostatic complementarity between the mAb antigen binding site and the p40 D1 domain epitope appears to play a key role in antibody/antigen recognition specificity. Interestingly, this structure also reveals significant structural differences in the p35 subunit and p35/p40 interface, compared with the published crystal structure of human IL-12, suggesting unusual and potentially functionally relevant structural flexibility of p35, as well as p40/p35 recognition. Collectively, these data describe unique observations about IL-12p35 and ustekinumab interactions with p40 that account for its dual binding and neutralization of IL-12 and IL-23.     

An artificial immune network based algorithm for diabetes diagnosis

A novel artificial immune network based algorithm for the diagnosis of diabetes is presented. The algorithm's implementation includes: (1) creating the initial immune antibody network; (2) the network is evolved with the learning from foreign antigens; (3) diagnosis process is accomplished by majority vote of the k nearest neighbor antibodies.     

Clinical characteristics of 26 human cases of highly pathogenic avian influenza A (H5N1) virus infection in China

Background

While human cases of highly pathogenic avian influenza A (H5N1) virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008.

Methodology/Principal Findings

Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6–62) and 58% were female. Many H5N1 cases reported fever (92%) and cough (58%) at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%), cardiac failure (50%), elevated aminotransaminases (43%), and renal dysfunction (17%). Fatal cases had a lower median nadir platelet count (64.5×10⁹ cells/L vs 93.0×10⁹ cells/L, p = 0.02), higher median peak lactic dehydrogenase (LDH) level (1982.5 U/L vs 1230.0 U/L, p = 0.001), higher percentage of ARDS (94% [n = 16] vs 56% [n = 5], p = 0.034) and more frequent cardiac failure (71% [n = 12] vs 11% [n = 1], p = 0.011) than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p = 0.003).

Conclusions/Significance

The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.