VA菌根真菌和大丽轮枝菌(Verticillium dahliae)对棉花体内PR蛋白的诱导作用

 植物对病原物侵害和多种逆境的普遍反应是合成病程相关蛋自(Pathogenesis-Related Proteins,PRs)。     

Megakaryocytes with intracytoplasmic blood cells

The phenomenon of megakaryocytes containing intracytoplasmic blood cells was frequently observed in the bone marrow of rats. The frequency appeared to increase in inflammatory or neoplastic conditions. The types of blood cells engulfed were mainly neutrophils. For the first time, megakaryocytes also were found to be engulfed.     

A miniature lighted stylet for fast oral endotracheal intubation in rabbits

Efficient oral endotracheal intubation of laboratory animals is a challenging technique in veterinary research. This study introduces a miniaturized lighted stylet for rabbit intubation. An experiment with repeated measures on two factors was used to assess the feasibility and efficacy of this method. The first factor compared stylet intubation vs. laryngoscopic intubation. The second compared three practitioners, one with prior experience and two without. Success rates on the initial attempt were not statistically different (χ² = 2.46, P = 0.12). The time difference between methods was significant (F = 41.007, P < 0.001), although the effect of practitioners was not (F = 1.038, P = 0.365). The mean ± SD of the intubation time, combining results from the three practitioners, was 20.34 ± 17.15 s for the stylet method and 57.58 ± 64.21 s for the laryngoscopic method. The results of this study demonstrate that lighted stylet intubation is efficient, robust, and independent of practitioner experience.     

Bacterial population in intestines of white shrimp,Litopenaeus vannamei fed a synbiotic containing Lactobacillus plantarum and galactooligosaccharide

The aims of this study were to unravel the intestinal microbiota of Litopenaeus vannamei after being fed a diet without (control) or with the synbiotic (SYN) for 60 days using next‐generation sequencing technology to see if changes in the intestinal microbiota were involved in the improved growth performance and health status of the shrimp. Next‐generation sequencing data showed that six phyla, 11 classes, 19 orders, 30 families, 58 genera and 73 species with taxonomic names assigned were detected. The majority of the operational taxonomic units (OTUs) was shared between the SYN and control shrimp and comprised 37 OTUs. However, intestinal biodiversity analyses revealed that SYN‐fed shrimp had a higher species richness, evenness and Shannon–Weaver index than did shrimp fed the control diet, but without reaching statistical significance. Interestingly, shrimp fed the SYN diet exhibited improved colonization of Lactobacillus plantarum and reduced prevalences of Vibrio harveyi and Photobacterium damselae in the intestines. These findings indicate that the SYN was able to modulate the intestinal bacterial community of shrimp and could be used to control vibriosis in shrimp.     

Effect of Barley β-Glucan in Durum Wheat Pasta on Human Glycemic Response

High-fiber, high-carbohydrate diets, including foods with low glycemic index, have been associated with prevention and treatment of diseases such as coronary heart disease and diabetes. β-glucan, a soluble, viscous polymer found in oat and barley endosperm cell wall, was incorporated into pasta test meals. Five fasted adult subjects were fed test meals of a barley and durum wheat blend pasta containing 100 g of available carbohydrate, 30 g of total dietary fiber (TDF) and 12 g of β-glucan, or an all durum wheat pasta containing the same amount of available carbohydrate, 5 g of TDF, and negligible β-glucan. The β-glucan and durum wheat pasta resulted in a lower glycemic response as measured by average total area and maximum increment of the blood glucose curves. Lower insulin response to the β-glucan and durum wheat pasta was also indicated by lower average area and increment characteristics of the insulin curves. Barley β-glucans may be an economical and palatable ingredient for processed food products formulated to modify glycemic and insulin response.     

In Vitro Bile‐Acid‐Binding of Whole vs. Pearled Wheat Grain

Health benefits of consuming whole grains are reduced risk of heart disease, stroke, and cancer. The U.S. Health and Human Services and USDA dietary guidelines recommend consumption of 6–10 oz of grain products daily and one‐half of that amount should contain whole grains. Whole grains contain vitamins, minerals, fiber, and phytonutrients. Bile‐acid‐binding capacity has been related to cholesterol lowering potential of food fractions. Lowered recirculating bile acids results in utilization of cholesterol to synthesize bile acid and reduced fat absorption. Secondary bile acids have been associated with increased risk of cancer. Bile‐acid‐binding potential has been related to lowering the risk of heart disease and that of cancer. It has been reported that bile‐acid‐binding of wheat bran is not related to its total dietary fiber (TDF) content. Whole (W) grain as well as pearled (P) hard red winter wheat (Hrw), hard white winter wheat (Hww), and durum wheat (DU) cooked grains were evaluated for in vitro, bile‐acid‐binding relative to cholestryramine (a cholesterol lowering bile‐acid‐binding drug). On dry matter basis (db) relative bile‐acid‐binding values were 7.7% WHrw; 7.5% WHww; 6.3% PHww; 6.0% PHrw; 5.5% WDU; and 5.4% PDU. On a TDF basis, binding values were 42–57% of that for cholestyramine for the whole and pearled wheat grains tested. Bile‐acid‐binding values (db) for WHrw and WHww were similar and significantly higher than those of PHww, PHrw, WDU and PDU. Similar bile‐acid‐binding of WHww to that of WHrw suggest that the red color commonly associated with whole grain may not necessarily indicate more healthful potential. Data suggest that cooked WHrw and WHww wheat have significantly higher health‐promoting potential than pearled grains. WDU or PDU wheat health‐promoting potential was similar to that of PHww or PHrw. Consumption of products containing WHrw and WHww are recommended.     

Expression of recombinant phytase of Bacillus subtilis E20 in Escherichia coli HMS 174 and improving the growth performance of white shrimp,Litopenaeus vannamei,juveniles by using phytase‐pretreated soybean meal‐containing diet

To produce a thermostable and neutral phytase (phy) of Bacillus subtilis E20 in Escherichia coli HMS174 and evaluate its efficiency in improving growth performance. The phy C of B. subtilis E20 was expressed in E. coli HMS 174, and then the 42‐kDa recombinant phy C was purified by Ni‐NAT and analysed by SDS–PAGE. The recombinant phy C had optimal ranges of pH of 6 ~ 7 and temperature of 50 ~ 60 °C. A thermostability analysis showed that the enzyme is a thermostable phytase, and around 33% of residual activity was detected after being incubated at 90 ~ 100 °C for 10 min. The recombinant phy C‐pretreated soybean meal for feed preparation improved white shrimp, Litopenaeus vannamei, growth and feed efficiency. Overall, the neutral and thermostable phy C is suitable for aquafeed, and it is able to improve the nutritional utilization, resulting in enhanced shrimp growth and reduced feed costs.     

小麦丛矮病研究之三:灰飞虱同发病的关系

1976—1977年河北晋县贺家寨大队小麦春季灰飞虱的传带病毒率为31—52%,不同地块同代灰飞虱的带毒率异差较大:而秋苗期则为12—35.4%,其中不同地块上同代(四代成虫)灰飞虱的带毒率的差异从33.3%至35.4%则不太大。灰飞虱的有效传毒指数(即虫口数×自然带毒率)同田间小麦发病率的相关性是非常显著的,其r=0.9769。1975—1976两年调查及计算分析结果,其直线回归公式如y=4.12x-2.577。在有效传毒指数0.7—20.9之间用于予测发病率有效。人工分期侵染试验证明小麦在生长发育过程中受侵愈早,病情愈重,其中死株率也愈大。秋季侵染的死株率达95.6%,病指为99.6;夏季侵染的死株率为0,病指为57.6。秋季小麦出苗前后的大量虫口形成小麦10月中下旬的一个发病高峰,第二年春季4月中旬的虫口高峰形成5月上旬的一个发病高峰。3月下旬的一个发病高峰是越冬前受侵的。病毒在小麦植株中的潜育期的长短随小麦的生长速度而异。温度不过其中因素之一,最短5—8天,最长30—40天。侵染后如小麦进入越冬期,即不表现症状,一直要到返青以后。介体灰飞虱在河北晋县以第五代3—4龄若虫在冬麦地及草荒中越冬。夏季在玉米上可以产卵并孵化,但不能长期存活,主要在地头沟边及夏作物荫蔽下的禾草上越夏。冬麦治虫防病的重点应在秋季麦苗出土前,春季则应在3月中旬左右。冬麦适当推迟播种有利于减少发病率。棉间作麦比平作的病情重六倍而粮麦间作的病情比平作的重九倍。     

Using Bacillus subtilis E20‐fermented soybean meal as replacement for fish meal in the diet of orange‐spotted grouper (Epinephelus coioides,Hamilton)

The potential of Bacillus subtilis E20‐fermented soybean meal (FSBM) as a partial alternative component of fish meal (FM) in fed diets of orange‐spotted grouper (Epinephelus coioides) was evaluated in this study. An FM‐based diet and seven diets containing 10%, 20% and 30% and 10%, 20%, 30% and 40% of FM replaced by soybean meal (SBM) and FSBM, respectively, were fed to grouper for 84 days to evaluate possible substitution levels of FM by tracking growth performance, digestive enzyme activity and morphological changes in the liver and distal intestine. No significant differences in survival and muscle composition of grouper were found between controls and treatments. Growth performance and feed efficiency of fish fed diets with FM replaced by FSBM up to 30% were not significantly different from controls, whereas significantly decreased growth performance and feed efficiency occurred with diets containing >20% of SBM. Based on the feed efficiency, the maximum substituted levels of FM by SBM and FSBM in grouper diets were 18.36% and 29.32%, respectively, based on broken‐line analyses. Histopathological changes in the liver and distal intestine, and significantly lower activity levels of digestive enzymes, including pepsin in the stomach and trypsin, chymotrypsin, amylase and lipase in the distal intestine, were found in fish fed a diet containing 30% of FM replaced by SBM. However, these parameters were improved by the substitution of FSBM. It is therefore believed that FSBM has great potential to be used as a protein source in grouper diets in partial replacement of FM.     

Schisandrin B protects against solar irradiation-induced oxidative injury in BJ human fibroblasts

The effects of schisandrin B (Sch B) and its analogs on solar irradiation-induced oxidative injury were examined in BJ human fibroblasts. Sch B and schisandrin C (Sch C) increased cellular reduced glutathione (GSH) level and protected against solar irradiation-induced oxidative injury. The photoprotection was paralleled by decreases in the elastases-type protease activity and matrix-metalloproteinases-1 expression in solar-irradiated fibroblasts. The cytochrome P-450-mediated metabolism of Sch B or Sch C caused ROS production. The results suggest that by virtue of its pro-oxidant action and the subsequent glutathione antioxidant response, Sch B or Sch C may offer the prospect of preventing skin photo-aging.