Baseline Sensitivity and Control Efficacy of Two Quinone Outside Inhibitor Fungicides, Azoxystrobin and Pyraclostrobin, Against Ustilaginoidea virens.

Rice false smut caused by the filamentous fungus Ustilaginoidea virens is a devastating grain disease in rice. Fungicides have been an important measure for the control of this disease. In this study, baseline sensitivities of 179 isolates of U. virens to the quinone outside inhibitor (QoI) fungicides azoxystrobin and pyraclostrobin were established. The distribution of the 50% effective concentration (EC50) values of each fungicide was unimodal. The frequency distribution of logarithmically transformed EC50 values fit or fit closer to a normal distribution. The ranges of EC50 values for azoxystrobin and pyraclostrobin were 0.001 to 0.864 and 0.001 to 0.569 µg/ml, with means and standard errors of the mean values of 0.203 ± 0.012 and 0.079 ± 0.006 µg/ml, respectively. There was a statistically significant and moderately positive correlation (n = 100, r = 0.469, P = 0.001) in sensitivity between these two fungicides. No cross-resistance was found between azoxystrobin, pyraclostrobin, and carbendazim or sterol demethylation inhibitor fungicides. Each fungicide had a significantly higher mean preventive efficacy compared with its curative efficacy. Field assays showed that the control efficacy of pyraclostrobin against rice false smut was greater than that of azoxystrobin. Pyraclostrobin had the best control of rice false smut in three rice varieties, with the control efficacy ranging from 81.5 to 95.5%, whereas azoxystrobin decreased the disease index by 64.1 to 69.2% under the same conditions. These results provide us a reference point in the management of U. virens and future QoI fungicide resistance monitoring programs.

Deletion of Krüppel-like factor-4 promotes axonal regeneration in mammals.

Axonal regeneration plays an important role in functional recovery after nervous system damage. However, after axonal injury in mammals, regeneration is often poor. The deletion of Krüppel-like factor-4 (Klf4) has been shown to promote axonal regeneration in retinal ganglion cells. However, the effects of Klf4 deletion on the corticospinal tract and peripheral nervous system are unknown. In this study, using a mouse model of sciatic nerve injury, we show that the expression of Klf4 in dorsal root ganglion sensory neurons was significantly reduced after peripheral axotomy, suggesting that the regeneration of the sciatic nerve is associated with Klf4. In vitro, dorsal root ganglion sensory neurons with Klf4 knockout exhibited significantly enhanced axonal regeneration. Furthermore, the regeneration of the sciatic nerve was enhanced in vivo following Klf4 knockout. Finally, AAV-Cre virus was used to knockout the Klf4 gene in the cortex. The deletion of Klf4 enhanced regeneration of the corticospinal tract in mice with spinal cord injury. Together, our findings suggest that regulating KLF4 activity in neurons is a potential strategy for promoting axonal regeneration and functional recovery after nervous system injury. This study was approved by the Animal Ethics Committee at Soochow University, China (approval No. SUDA20200316A01).

Inhibition of PTEN activity promotes IB4-positive sensory neuronal axon growth.

Traumatic nerve injuries have become a common clinical problem, and axon regeneration is a critical process in the successful functional recovery of the injured nervous system. In this study, we found that peripheral axotomy reduces PTEN expression in adult sensory neurons; however, it did not alter the expression level of PTEN in IB4-positive sensory neurons. Additionally, our results indicate that the artificial inhibition of PTEN markedly promotes adult sensory axon regeneration, including IB4-positive neuronal axon growth. Thus, our results provide strong evidence that PTEN is a prominent repressor of adult sensory axon regeneration, especially in IB4-positive neurons.

c-Myc controls the fate of neural progenitor cells during cerebral cortex development.

The anatomical structure of the mammalian cerebral cortex is the essential foundation for its complex neural activity. This structure is developed by proliferation, differentiation, and migration of neural progenitor cells (NPCs), the fate of which is spatially and temporally regulated by the proper gene. This study was used in utero electroporation and found that the well-known oncogene c-Myc mainly promoted NPCs' proliferation and their transformation into intermediate precursor cells. Furthermore, the obtained results also showed that c-Myc blocked the differentiation of NPCs to postmitotic neurons, and the expression of telomere reverse transcriptase was controlled by c-Myc in the neocortex. These findings indicated c-Myc as a key regulator of the fate of NPCs during the development of the cerebral cortex.

Calcium/calmodulin-dependent protein kinase II regulates mammalian axon growth by affecting F-actin length in growth cone.

While axon regeneration is a key determinant of functional recovery of the nervous system after injury, it is often poor in the mature nervous system. Influx of extracellular calcium (Ca2+ ) is one of the first phenomena that occur following axonal injury, and calcium/calmodulin-dependent protein kinase II (CaMKII), a target substrate for calcium ions, regulates the status of cytoskeletal proteins such as F-actin. Herein, we found that peripheral axotomy activates CaMKII in dorsal root ganglion (DRG) sensory neurons, and inhibition of CaMKII impairs axon outgrowth in both the peripheral and central nervous systems (PNS and CNS, respectively). Most importantly, we also found that the activation of CaMKII promotes PNS and CNS axon growth, and regulatory effects of CaMKII on axon growth occur via affecting the length of the F-actin. Thus, we believe our findings provide clear evidence that CaMKII is a critical modulator of mammalian axon regeneration.

Regulation of adult mammalian intrinsic axonal regeneration by NF-κB/STAT3 signaling cascade.

The inflammatory response is a critical regulator for the regeneration of axon following nervous system injury. Nuclear factor-kappa B (NF-κB) is characteristically known for its ubiquitous role in the inflammatory response. However, its functional role in adult mammalian axon growth remains elusive. Here, we found that the NF-κB signaling pathway is activated in adult sensory neurons through peripheral axotomy. Furthermore, inhibition of NF-κB in peripheral sensory neurons attenuated their axon growth in vitro and in vivo. Our results also showed that NF-κB modulated axon growth by repressing the phosphorylation of STAT3. Furthermore, activation of STAT3 significantly promoted adult optic nerve regeneration. Taken together, the findings of our study indicated that NF-κB/STAT3 cascade is a critical regulator of intrinsic axon growth capability in the adult nervous system.

Comparison of postoperative complications between internal and external pancreatic duct stenting during pancreaticoduodenectomy: a meta-analysis.

BACKGROUND: Two types of pancreatic duct stents are used to improve postoperative outcomes of pancreatic anastomosis. The aim of this meta-analysis was to evaluate and compare the postoperative outcomes of patients with internal or external stenting during pancreaticoduodenectomy (PD). METHODS: We searched PubMed, EMBASE, the Cochrane Library and Web of Science databases until the end of December, 2014. Studies comparing outcomes of external vs. internal stent placement in PD were eligible for inclusion. Included literature was extracted and assessed by two independent reviewers. RESULTS: Seven articles were identified for inclusion: three randomized controlled trials (RCTs) and four observational clinical studies (OCS). The meta-analyses revealed that use of external stents had advantage on reducing the incidences of pancreatic fistula (PF) in total [odds ratio (OR) =0.69; 95% confidence interval (CI), 0.48-0.99; P=0.04], PF in soft pancreas (OR =0.30; 95% CI, 0.16-0.56; P=0.0002) and delayed gastric emptying (DGE) (OR =0.58; 95% CI, 0.38-0.89; P=0.01) compared with internal stents. There were no significant differences in other postoperative outcomes between two stenting methods, including postoperative morbidity (OR =0.93; 95% CI, 0.39-2.23; P=0.88), overall mortality (OR =0.70; 95% CI, 0.22-2.25; P=0.55), and intra-abdominal collections (OR =0.67; 95% CI, 0.26-1.71; P=0.40). CONCLUSIONS: Based upon this meta-analysis, the use of external pancreatic stents might have potential benefit in reducing the incidence of PF and DGE. Due to the limited number of original studies, more RCTs are needed to further support our result and clarify the issue.

[Response of yield, quality and nitrogen use efficiency to nitrogen fertilizer from mechanical transplanting super japonica rice].

Five super japonica rice cultivars were grown by mechanical transplanting in field and seven N treatments with total N application rate of 0, 150, 187.5, 225, 262.5, 300 and 337.5 kg x hm(-2) respectively were adopted to study the effects of N rate on rice yield, quality and N use efficiency. The differences between N requirement for obtaining the highest yield and for achieving the best economic benefit were compared. With the increase of N fertilizer rate, the yields of five super japonica rice cultivars increased firstly and then descended, achieving the highest yield at the N level of 300 kg x hm(-2) ranging from 10.33-10.60 kg x hm(-2). Yield increase mainly attributed to the large number of spikelet, for the total spikelet number of each rice cultivar reached the maximum value at the 300 kg x hm(-2) N level. With the increase of N application, the rates of brown rice, milled rice, head milled rice and the protein content of the five super japonica rice cultivars were all increased, and the rates of brown rice, milled rice, head milled rice and the protein con- tent were higher at 337.5 kg x hm(-2) N level than at 0 kg x hm(-2) N level by 3.3%-4.2%, 2.9%-6.0%, 4.4%-33.7% and 23.8%-44.3%, respectively. While the amylose content, gel consistency and taste value of the five rice cultivars were all decreased, and the amylose content, gel consistency and taste value were lower at 337.5 kg x hm(-2) N level than at 0 kg x hm(-2) N level by 12.4%-38.9%, 10.3%-28.5% and 20.3%-29.7%, respectively. The chalkiness increased firstly and then decreased while the change of chalky rate varied with the cultivars. With the increase of N application, the N use efficiency, agronomic N use efficiency and physiological N use efficiency decreased while the N uptake of grain increased significantly. If the cost of N fertilizer was taken into account, the N fertilizer amount to obtain the optimal economic benefits would be 275.68 kg x hm(-2) with the corresponding yield of 9.97 t x hm(-2). Therefore, in the existing super rice production, classified management of N fertilizer would be required to meet differentiated demands of high yield, good quality, high efficiency, low N fertilizer input and so on.

Survey of antioxidant capacity and phenolic composition of blueberry, blackberry, and strawberry in Nanjing.

Berries are a good source of natural antioxidants. In the present study, the total antioxidant capacity and phenolic composition of three berry fruits (blueberry, blackberry, and strawberry) cultivated in Nanjing were investigated. Blueberry, with a Trolox equivalent antioxidant capacity (TEAC) value of 14.98 mmol Trolox/100 g dry weight (DW), exhibited the strongest total antioxidant capacity using both the 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods. Blueberry also had the highest total phenolic content (TPC, 9.44 mg gallic acid/g DW), total flavonoid content (TFC, 36.08 mg rutin/g DW), and total anthocyanidin content (TAC, 24.38 mg catechin/g DW). A preliminary analysis using high performance liquid chromatography (HPLC) showed that the blueberry, blackberry, and strawberry samples tested contained a range of phenolic acids (including gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, p-coumaric acid, ferulic acid, ellagic acid, and cinnamic acid) and various types of flavonoids (flavone: luteolin; flavonols: rutin, myricetin, quercetrin, and quercetin; flavanols: gallocatechin, epigallocatechin, catechin, and catechin gallate; anthocyanidins: malvidin-3-galactoside, malvidin-3-glucoside, and cyanidin). In particular, the blueberries had high levels of proanthocyanidins and anthocyanidins, which might be responsible for their strong antioxidant activities. These results indicate a potential market role for berries (especially blueberries) as a functional food ingredient or nutraceutical.

[Silicon application enhances resistance to sheath blight (Rhizoctonia solani) in rice].

The enhancing resistance and decreasing incidence to sheath blight (Rhizoctonia solani) by silicon were studied from cytological and physiological aspects by using rice plants solution-cultured with silicon supplementation or with silicon-deficiency. By an environmental scanning electron coupled with X-ray microanalysis, as well as gravimetric quantification, the number of siliceous cell and Si content of the Si(+) rice leaf were much more than those of Si(-) rice leaf (Figs.1,2; Table 1). After being inoculated with R. solani MDA content in Si(+) rice plants was almost higher than that in Si(-) rice plants, SOD activity in Si(+) rice plants was always higher than that in Si(-) rice plants, SOD activity in Si(+) rice plants reached a minimum on 4 d, and POD activity was at the maximum, but POD activity in Si(-) rice plants was lower. These results suggested that silicon could enhance the harmony of SOD and POD. And silicon had no effect on CAT and PAL activity, but weaken PPO activity (Fig.3). After being inoculated with R. solani, the Si(+) rice plants had significantly lower disease index with relative control effect of 1/4 compared to the Si(-) rice plants (Table 2).