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An outbreak of grey leaf spot caused by Stemphylium solani was observed on tomato in Shandong Province of China in recent years and brought huge economical losses. Fludioxonil is a phenylpyrrole fungicide with strong antifungal activity against S. solani. To evaluate the risk of S. solani developing fludioxonil resistance, a total of 145 field isolates were examined for sensitivity to fludioxonil by measuring mycelial growth. The baseline sensitivity was distributed as a unimodal curve with a mean EC50 value of 0.0659 (±0.0170) µg mL−1. Five mutants with high resistance to fludioxonil (RF > 1000) were obtained by successively selecting on fludioxonil-amended plates in the laboratory. All the resistant mutants associated with strongly reduced fitness in mycelial growth, sporulation and pathogenicity. Fludioxonil had positive cross-resistance with procymidone and iprodione, but there was no cross-resistance with other fungicides including boscalid, fluazinam, azoxystrobin and flusilazole. Based on the current results, resistance risk of S. solani to fludioxonil could be moderate. This is the first report of baseline sensitivity of S. solani to fludioxonil and its risk assessment. In order to delay the resistance development, it is recommended that fludioxonil can be used as one component of the mixture or fungicides with different modes of action should be alternatively used for this disease management.

Mutant SOD1 causes amyotrophic lateral sclerosis (ALS) by a dominant gain of toxicity. Previous studies have demonstrated therapeutic potential of mutant SOD1-RNAi delivered by intrathecal (IT) injection of recombinant adeno-associated virus (rAAV). However, optimization of delivery is needed to overcome the high degree of variation in the transduction efficiency and therapeutic efficacy. Here, on the basis of our previously defined, efficient IT injection method, we investigated the influence of injection speed on transduction efficiency in the central nervous system (CNS). We demonstrate that slow IT injection results in higher transduction of spinal cord and dorsal root ganglia (DRG) while fast IT injection leads to higher transduction of brain and peripheral organs. To test how these effects influence the outcome of RNAi therapy, we used slow and fast IT injection to deliver rAAVrh10-GFP-amiR-SOD1, a rAAV vector that expresses GFP and an artificial miRNA targeting SOD1, in SOD1-G93A mice. Both slow and fast IT injection produced therapeutic efficacy but the slow injection trended slightly towards a better outcome than the fast injection. These results demonstrate that IT injection speed influences the predominance of gene delivery at different CNS sites and should be taken into consideration in future therapeutic trials involving intrathecal injection.

Y5247 (development code no.), a quinone-outsider-inhibitor (QoI), is a novel fungicide with a broad-spectrum of fungicidal activity against plant filamentous fungi, including B. cinerea. Compared to azoxystrobin, Y5247 had a stronger inhibitory effect on mycelial growth of B. cinerea. The baseline sensitivity of 100 strains showed the EC50 values for Y5247 inhibiting mycelial growth of B. cinerea ranged from 0.0033 to 0.3921 μg/mL with a mean of 0.0859 (±0.0788) μg/mL and the frequency distribution of EC50 values was unimodal. Mutants with stable resistance to Y5247 were not obtained following exposure to ultraviolet light or chemical mutagenesis. However, strains resistant to Y5247 were collected from greenhouses where other QoI fungicides had frequently been sprayed to control gray mold of strawberry. Among the Y5247-resistant strains, EC50 values for Y5247 and other QoIs, including azoxystrobin, kresoxim-methyl and pyraclostrobin, were positively correlated. No cross-resistance was detected between Y5247 and the other fungicides with different modes of action such as carbendazim, diethofencarb, boscalid, fluazinam, procymidone, and fludioxonil. The Y5247-resistant strains showed comparable fitness in mycelial growth, sporulation and pathogenicity to that of Y5247-sensitive strains. The risk of B. cinerea developing resistance to Y5247 was assessed as high. Analysis of cytb in B. cinerea showed that all the Y5247-sensitive and resistant strains carried the type II cytb (which lacks the intron Bcbi-143/144) and the point mutation G143A occurred in all the resistant strains tested.

SYP-1620, a quinone-outside-inhibitor (QoI), is a novel broad-spectrum fungicide. In this study, 108 isolates of Botrytis cinerea from different geographical regions in Jiangsu Province of China were characterized for baseline sensitivity to SYP-1620. The curves of baseline sensitivity were unimodal with a mean EC50 value of 0.0130±0.0109 μg/mL for mycelial growth, 0.01147±0.0062 μg/mL for spore germination, respectively. The biological characterization of SYP-1620 against B. cinerea was determined in vitro. The results indicated that SYP-1620 has a strong inhibiting effect on spore germination, mycelial growth, and respiration. The protective and curative test of SYP-1620 suggested that protective effect was better than curative either on strawberry leaves or on cucumber leaves in vivo. In addition, the biological characterization of SYP-1620-resistant mutants of B. cinerea was investigated. SYP-1620 has no cross-resistance with other types of fungicide. Compared to the sensitive isolates, the resistant mutants had lower mycelial growth and virulence but not differ in mycelial dry weight. Sequencing indicated that SYP-1620 resistance was associated with a single point mutation (G143A) in the cytochrome b gene.

Fluorescence spectra and signal stability of the fluorescent scale inhibitor SC260 and dibenzofuran-2-sulfonic acid hydrate in deionized water and in seawater concentration experiment were described. There was no impact on respective excitation and emission peaks of each other and the change of fluorescence intensity was no more than 5%. The relationship between fluorescence intensity and concentration of SC260 and BFN were linear. Because the fluorescence signals of SC260 and BFN were stable in seawater concentration experiment, the consumption of fluorescent inhibitor SC260 in seawater was studied.

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disease involving both upper and lower motor neurons. The mechanism of motor neuron degeneration is still unknown. Although many studies have been performed on spinal motor neurons, few have been reported on brainstem and its motor nuclei. The aim of this study was to investigate oxidative stress and autophagic changes in the brainstem and representative motor nuclei of superoxide dismutase 1 (SOD1)-G93A mouse model of ALS. The expression levels of cluster of differentiation molecule 11b (CD11b), glial fibrillary acidic protein, glutamate-cysteine ligase catalytic subunit, heme oxygenase-1, NAD(P)H: quinone oxidoreductase 1, voltage-dependent anion-selective channel protein 1, Sequestosome 1/p62 (p62), microtubule-associated protein 1 light chain 3B (LC3), and SOD1 proteins in brainstem were examined by Western blot analysis. Immunohistochemistry and immunofluorescence were performed to identify the cellular localization of SOD1, p62, and LC3B, respectively. The results showed that there were progressive asctrocytic proliferation and microglial activation, induction of antioxidant proteins, and increased p62 and LC3II expression in brainstem of SOD1-G93A mice. Additionally, SOD1 and p62 accumulated in hypoglossal, facial, and red nuclei, but not in oculomotor nucleus. Furthermore, electron microscope showed increased autophagic vacuoles in affected brainstem motor nuclei. Our results indicate that brainstem share similar gliosis, oxidative stress, and autophagic changes as the spinal cord in SOD1-G93A mice. Thus, SOD1 accumulation in astrocytes and neurons, oxidative stress, and altered autophagy are involved in motor neuron degeneration in the brainstem, similar to the motor neurons in spinal cord. Therefore, therapeutic trials in the SOD1G93A mice need to target the brainstem in addition to the spinal cord.

Experimental autoimmune gray matter disease (EAGMD) is a model of both upper and lower motor neuron degeneration. EAGMD and amyotrophic lateral sclerosis (ALS) possess similar clinical and pathological features. The aim of this study was to find evidence of upper and lower neuronal damage in the EAGMD guinea pigs. The main ultrastructural alterations included abnormal mitochondria and disorganization of neurofilaments in the myelinated nerve fibers of the spinal cord. Swollen mitochondria and dilated endoplasmic reticulum were found in pyramidal cells of the motor cortex. The myelinated fibers in the cerebral peduncle showed atrophied axons and swollen mitochondria. Some motoneurons showed apoptosis-like signs. Pathological changes in the sciatic nerve manifest wallerian-like degeneration. Using immunofluorescence double labeling and confocal laser microscopy, IgG was colocalized with activated microglia in the ventral horn of the spinal cord. We also examined possible evidences of oxidative stress in the EAGMD guinea pig model and the role of p38 mitogen-activated protein kinase (p38MAPK) pathway in motor neuron degeneration. Our findings suggest that nitric oxide and peroxynitrite-mediated oxidative damage may play important roles in the pathogenesis of the neuronal degeneration in the spinal cord. Inflammatory cytokines such as TNF-α and IL-1 play important roles in the formation and acceleration of the spinal cord damage. The activation of p38MAPK signal pathway was involved in the development of the motor neuron degeneration of the spinal cord.

In order to clarify the effects of tillage patterns on farmland weed community structure and crop production characteristics, based on 10 years location experiment with no-tillage, subsoiling and conventional tillage in the cold and arid region of North China, and supplementary experiment of plowing after 10 years no-tillage and subsoiling, oat was planted in 2 soils under different tillage patterns, and field weed total density, dominant weed types, weed diversity index, field weed biomass and oats yield were measured. The results showed that the regional weed community was dominated by foxtail weed (Setaira viridis); the weed density under long-term no-tillage was 2.20-5.14 times of tillage at different growing stages of oat, but there were no significant differences between conditional tillage and plowing after long-term no-tillage and subsoiling. Field weed Shannon diversity indices were 0.429 and 0.531, respectively, for sandy chestnut soil and loamy meadow soil under no-tillage conditions, and field weed biomass values were 1.35 and 2.26 times of plowing treatment, while the oat biomass values were only 2807.4 kg x hm(-2) and 4053.9 kg x hm(-2), decreased by 22.3% and 46.2%, respectively. The results showed that the weed community characteristics were affected by both tillage patterns and soil types. Long-term no-tillage farmland in the cold and arid region of North China could promote the natural evolution of plant communities by keeping more perennial weeds, and the plowing pattern lowered the annual weed density, eliminated perennial weeds with shallow roots, and stimulated perennial weeds with deep roots.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by selective motor neuron death. We report the characteristics of ultrastructural pathological changes of inclusions and aggregations in the neuronal axons, glial cells and ventral roots of lumbar spinal cord in SOD1-G93A transgenic mice using light and electron transmission microscope at different stages of disease. The most noteworthy is that mutant SOD1 accumulations in the cytoplasm of motor neurons precede the numerous inclusions. Inclusions manifested differently according to the specified locations. This study provided further information to the previous reports about pathological changes of ALS.

A subset of patients of amyotrophic lateral sclerosis (ALS) present with mutation of Cu/Zn superoxide dismutase 1 (SOD1), and such mutants caused an ALS- like disorder when expressed in rodents. These findings implicated SOD1 in ALS pathogenesis and made the transgenic animals a widely used ALS model. However, previous studies of these animals have focused largely on motor neuron damage. We report herein that the spinal cords of mice expressing a human SOD1 mutant (hSOD1-G93A), besides showing typical destruction of motor neurons and axons, exhibit significant damage in the sensory system, including Wallerian-like degeneration in axons of dorsal root and dorsal funiculus, and mitochondrial damage in dorsal root ganglia neurons. Thus, hSOD1-G93A mutation causes both motor and sensory neuropathies, and as such the disease developed in the transgenic mice very closely resembles human ALS.

Observational cross-section study. The objective of our study was to determine if phosphorylation of aggregated neurofilaments (NFs) would occur in autoimmune-mediated motor neuron injury. Our main hypothesis was that autoimmune-mediated damage of spinal cord motor neurons may influence NF phosphorylation and lead to NF aggregation. A total of 20 guinea pigs were inoculated with bovine spinal cord anterior horn homogenates (experimental autoimmune gray matter model) and 20 guinea pigs were inoculated with phosphate-buffered saline (control). NF phosphorylation and aggregation were observed by immunohistochemistry and electron microscopic examination. Data were analyzed using Student's t-test with P

Recent evidence indicates that neuroinflammation is a key event in amyotrophic lateral sclerosis (ALS). However, the precise impact of inflammation on motor neurons remains elusive. By using organotypic spinal cord slice cultures, we demonstrate that exposure to lipopolysaccharide (LPS) led to the demise of motor neurons in a dose- and time- dependent manner, whereas interneurons were impaired relatively mildly. The ultrastructure of motor neurons showed extensive vacuolation and swollen mitochondria. Motor neurons lacked the expression of calretinin, and BAPTA-AM, an intracellular calcium chelator, ameliorated motor neuron injury, indicating that the low capacity of calcium buffering may partially account for the vulnerability of motor neurons. NADPH oxidase was activated upon LPS challenge, and apocynin, the selective inhibitor of this enzyme, prevented inflammation-mediated toxicity to motor neurons, suggesting that NADPH oxidase may play a critical role in motor neuron death caused by LPS-induced inflammation.

(1) Phase II enzyme inducer is a kind of compound which can promote the expression of antioxidative enzymes through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Recently, it has been reported that these compounds show neuroprotective effect via combating oxidative stress. The purpose of this study is to determine whether phase II enzyme inducers have neuroprotective effects on traumatic spinal cord injury. (2) An organotypic spinal cord culture system was used, Phase II enzyme inducers were added to culture medium for 1 week, motor neurons were counted by SMI-32 staining, glutamate, Nrf2, and Heme oxygenase-1(HO-1) mRNA were tested. (3) This study showed motor neuron loss within 1 week in culture. After 1 week in culture, the system was stable. Moreover, Glutamate was increased when in culture 48 h and decreased after 1 week in culture. There was no significant change between 1 and 4 weeks in culture. Necrotic motor neuron and damaged mitochondrial were observed in culture 48 h. Furthermore, phase II enzyme inducers: tert-butyhydroquinone (t-BHQ), 3H-1,2-dithiole-3-thione (D3T), and 5,6-dihydrocyclopenta-1,2-dithiole-3-thione (CPDT) were shown to promote motor neuron survival after dissection, it was due to increasing Nrf2 and HO-1 mRNA expression and protecting mitochondrial not due to decreasing glutamate level. (4) The loss of motor neuron due to dissection can mimic severe traumatic spinal cord injury. These results demonstrate that glutamate excitotoxicity and the damage of mitochondrial is possibly involve in motor neuron death after traumatic spinal cord injury and phase II enzyme inducers show neuroprotective potential on motor neuron survival in traumatic spinal cord injury in vitro.