Microbiological Identification and Analysis of Swine Lungs Collected from Carcasses in Swine Farms, China

The primary objective of this 3 years study was to determine the prevalence of porcine pathogens of the lungs of swine in swine farms in southern China. A total of 5,420 samples were collected from 200 swine farms. The bacterium that was most commonly isolated was Streptococcus suis, with 10.24 % of the samples being positive, 114 lungs (2.1 %) were positive for pseudorabies virus and 263 (4.85 %) were positive for classical swine fever virus; much lower than positive for PRRSV (15.1 %, p = 0.023) and PCV2 (13.8 %, p = 0.038). lungs that were positive for PRRSV and/or PCV-2 have significantly increased odds of being positive for any of the S. suis (9.79 vs. 0.44 %, p = 0.003).     

Silica retention in the Three Gorges Reservoir

A mass balance of dissolved silica (DSi) based on daily measurements at the inflow and outflow of the Three Gorges Reservoir (TGR) in 2007 and a more precise budget, with inflow, outflow, primary production, biogenic silica (BSi) settlement, dissolution of BSi in the water column and flux of DSi at the sediment–water interface in the dry season (April) of 2007 were developed. We address the following question: How much does the Three Gorges Dam (TGD) affect silica transport in the TGR of the Changjiang River (Yangtze River)? The DSi varied from 71.1 to 141 μmol/l with an average of 108 μmol/l, and it ranged between 68.1 and 136 μmol/l, with an average of 107 μmol/l in inflow and outflow, respectively, in the TGR in 2007. The linear relationship of DSi between inflow and outflow water is significant (r = 0.87, n = 362, p < 0.01). Along the main stream of the TGR, the DSi concentration decreases with an average concentration of 84.0 μmol/l in the dry season. However, the stratification of DSi was not obvious in the main channel of the TGR in the dry season. The BSi is within the range of 0.04–5.00 μmol/l, with an average concentration of 2.1 μmol/l in the main channel of the TGR, while it is much higher in Xiangxi Bay (1.30–47.7 μmol/l, 13.1 μmol/l) than in the main stream of the TGR and the other bays. After the third filling of the TGR, approximately 3.8% of the DSi was retained by the TGR based on a 12-month monitoring scheme in 2007, which would slightly reduce nutrient fluxes of the Changjiang River to the East China Sea (2%). DSi was lost during January to June and November, whereas the additions of DSi were found during the other months in 2007. The budget results also indicate that there is a slight retention of DSi. The retention of DSi in the reservoir is approximately 2.9%, while BSi is approximately 44%. Compared with the total silica load, the retention of DSi and BSi in the reservoir is only 5.0% in the dry season. With its present storage capacity, the reservoir does not play an important role as a silica sink in the channel of the TGR. The DSi load is significantly related to discharge both in inflow and outflow waters (p < 0.01). DSi retention, to some extent, is the runoff change due to impoundment.     

黄精种子萌发过程发育解剖学研究

采用石蜡切片技术对成熟黄精种子形态及萌发过程中的形态学变化及解剖结构特征进行了研究,以阐明黄精种子繁殖的生物学机制。结果显示:(1)成熟的黄精种子由外而内依次为种皮、胚乳和胚等3部分组成。其中种皮由一层木质化的细胞组成;胚乳占据种子的大部分结构,胚乳细胞含有大量淀粉,细胞壁增厚;胚处于棒型胚阶段。(2)黄精种子在萌发过程中棒型胚靠近种脐端分化为吸器、子叶联结和子叶鞘,靠近种孔的部位分化出胚根、胚轴和胚芽。(3)黄精种子萌发首先由子叶联结伸长将胚芽和胚根原基推出种孔,紧接着下胚轴膨大形成初生小根茎,吸器留在种子中分解吸收胚乳中的营养物质。(4)通过子叶联结连通吸器和初生小根茎,将胚乳中的营养物质由吸器-子叶联结这个通路转移到初生小根茎中,为初生根茎上胚芽和胚根的进一步分化提供物质保障。(5)黄精种子自然条件下萌发率较低,而且当年不出土。研究表明,黄精种子的繁殖生物学特性是其生态适应的一种重要机制。     

A Dual-Mode Surface Display System for the Maturation and Production of Monoclonal Antibodies in Glyco-Engineered Pichia pastoris

State-of-the-art monoclonal antibody (mAb) discovery methods that utilize surface display techniques in prokaryotic and eukaryotic cells require multiple steps of reformatting and switching of hosts to transition from display to expression. This results in a separation between antibody affinity maturation and full-length mAb production platforms. Here, we report for the first time, a method in Glyco-engineered Pichia pastoris that enables simultaneous surface display and secretion of full-length mAb molecules with human-like N-glycans using the same yeast cell. This paradigm takes advantage of homo-dimerization of the Fc portion of an IgG molecule to a surface-anchored "bait" Fc, which results in targeting functional “half” IgGs to the cell wall of Pichia pastoris without interfering with the secretion of full length mAb. We show the utility of this method in isolating high affinity, well-expressed anti-PCSK9 leads from a designed library that was created by mating yeasts containing either light chain or heavy chain IgG libraries. Coupled with Glyco-engineered Pichia pastoris , this method provides a powerful tool for the discovery and production of therapeutic human mAbs in the same host thus improving drug developability and potentially shortening the discovery time cycle.     

Root over-production in heterogeneous nutrient environment has no negative effects on Zea mays shoot growth in the field

Plant and Soil - Nutrient patches in soil have a limited life-span, but the long-term costs and benefits of root foraging in agro-ecological systems are poorly understood. Maize (Zea mays L) was...     

Cytotoxic Spliceostatin Analogs from Pseudomonas sp.

Two new spliceostatin analogs, designed as spliceostatins J and K ( 1 and 2 ), were isolated and identified from the culture of Pseudomonas sp., along with two known ones, FR901464 ( 3 ) and spliceostatin E ( 4 ). Their structures were elucidated by detailed interpretation of their spectroscopic data, especially 2D‐NMR and HR‐ESI‐MS. Spliceostatin J ( 1 ) represented the first example of spliceostatins bearing an unusual hexahydrofuro[3,4‐b]furan moiety. Biological assay showed all the isolated compounds except 1 displayed potent cytotoxic activities against two cancer cell lines (MDA‐MB‐231 and A‐549). Structure‐activity‐relationship studies revealed that the tetrahydropyran ring in spliceostatin analogs was necessary for their bioactive retention.     

New Immunomodulating Polyhydroxypregnane Glycosides from the Roots of Cynanchum otophyllum C.K.Schneid.

Seven new polyhydroxypregnane glycosides, named cynotophyllosides P–V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid . Their structures were elucidated by a variety of spectroscopic techniques, as well as acid‐catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A‐ and LPS‐induced proliferation of mice splenocytes. Immunoenhancing (for 1 , 9 ) and immunosuppressive (for 2 ) activities were observed. Furthermore, cynotophylloside R ( 3 ) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 μg/ml.     

Dysregulated expression of ACTN4 contributes to endothelial cell injury via the activation of the p38-MAPK/p53 apoptosis pathway in preeclampsia

Journal of Physiology and Biochemistry - Preeclampsia (PE) is a hypertensive disease associated with increased endothelial cell dysfunction caused by systemic oxidative stress. Alpha-actinin-4...     

A thiol-inducible and quick-response DNA cross-linking agent

Three new 2,4-dinitrobenzenesulfonyl derivatives 1–3 were successfully prepared for the first time using a simple process. They were efficiently triggered by thiols (glutathione and l-cysteine) to release the corresponding phenol derivatives (4–6) within 5?min. The quick response of 1–3 toward thiols was determined by ¹H NMR and HPLC. Moreover, our results indicated that 1 could induce DNA cross-linking in the presence of glutathione, probably due to the quinone methide formation of phenol intermediate 4 followed by departure of 2,4-dinitrobenzenesulfonyl group.