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A novel neurological disorder, shaking mink syndrome (SMS), emerged in Denmark and Sweden in 2000. SMS has seldom been reported in China, but the causative agent has not been detected in the country. SMS outbreaks occurred in multiple provinces in 2020. A total of 44 brain samples from minks associated with SMS were collected from Heilongjiang, Liaoning and Shandong provinces of which 28 samples (63.3%) were SMS‐astrovirus (SMS‐AstV)‐positive by reverse transcription PCR. Histopathological examination revealed non‐suppurative encephalitis in three minks. Moreover, the complete coding region sequences (CDSs, 6559 bp) of a sample collected from a 2‐month‐old mink (termed SMS‐AstV‐H1, GSA accession No. SAMC816786) were amplified by PCR and Sanger sequencing. The complete CDS and open reading frame 2 sequences of SMS‐AstV‐H1 were 94.3% and 96.4% identical to an SMS‐AstV strain (GenBank accession number: GU985458). Phylogenetically, SMS‐AstV‐H1 was closely related to an SMS‐AstV strain (GU985458). Based on the above results, we describe SMS‐AstV‐associated encephalitis in farmed minks in China. Future studies need to focus on epidemiology, virus isolation and potential interspecies transmission of SMS‐AstV. [ABSTRACT FROM AUTHOR]

Most patients with DFU need to regularly visit healthcare providers to receive adequate wound care and obtain the maintenance medications for diabetes. All patients should be first screened for the COVID-19 infection if they have respiratory syndrome and/or history of close contact with confirmed cases. To minimize the potential risks of nosocomial COVID-19 infection, once there are early signs of DFI improvement, patients are discharged to receive home care similarly as patients with mild infection. [Extracted from the article]

No study has investigated the role of induced membrane (IM) formation in treating diabetic foot ulcer (DFU). This retrospective study was aimed (1) at evaluating the potential role of a two-staged surgical approach, comprising polymethylmethacrylate (PMMA) implantation and IM formation, in the treatment of DFU and (2) at comparing the results of those with routine wound debridement in patients with DFUs and nonrevascularized peripheral arterial disease (PAD). Fifty patients with infected DFUs who were not candidates for vascular interventions were enrolled between February 2016 and April 2018 and assigned to the PMMA group (n=28) and conventional group (n=22). The healing rate, major amputation rate, duration of healing, frequency of debridement procedures, patient survival rate, and reulceration of DFUs were determined. The Mann-Whitney U test, independent sample t-test, and χ2 or Fisher exact test were used in statistical analysis. Overall clinical outcomes were statistically different between the groups (Z=−2.495, P=0.013). In the PMMA group, 16 patients (57.1%) with intact IM formation achieved ulceration healing at 13.1±3.7 weeks with a mean number of debridements of 1.3±0.4, which were significantly different compared to those values in 5 patients of the conventional group (22.7%, P=0.014; healing duration: 26.4±7.8 weeks, P=0.016; mean number of debridements: 3.6±0.5, P≤0.001). At a mean 16.8±4.3-month follow-up, patient survival rates were 92.9% and 68.2% in the PMMA and conventional groups, respectively (P=0.032). The major amputation rate and reulceration of DFUs were similar between the groups. The two-staged surgical approach is an available, effective modality for improving healing of DFUs. This study provides preliminary information of IM formation followed by PMMA implantation in the management of DFUs in PAD when revascularization is not feasible. [ABSTRACT FROM AUTHOR]

There has been growing interest in using microalgae as production hosts for a wide range of value‐added compounds. However, microalgal genetic improvement is impeded by lack of genetic tools to concurrently control multiple genes. Here, we identified two novel strong promoters, designated Pt202 and Pt667, and delineated their potential role on simultaneously driving the expression of key lipogenic genes in Phaeodactylum tricornutum. In silico analyses of the identified promoter sequences predicted the presence of essential core cis elements such as TATA and CAAT boxes. Regulatory role of the promoters was preliminarily assessed by using GUS reporter which demonstrated strong GUS expression. Thereafter, two key lipogenic genes including malic enzyme (PtME) and 5‐desaturase (PtD5b), were overexpressed by the two promoters Pt202 and Pt667, respectively, in P. tricornutum. Combinatorial gene overexpression did not impair general physiological performance, meanwhile neutral lipid content was remarkably increased by 2.4‐fold. GC‐MS analysis of fatty acid methyl esters revealed that eicosapentaenoic acid (EPA; C20:5) was increased significantly. The findings augment a crucial kit to microalgal genetic tools that could facilitate the multiple‐gene expression driven by various promoters, and promote microalgae for industrial bioproduction. [ABSTRACT FROM AUTHOR]

Oleaginous microalgae hold great promises for biofuel production. However, commercialization of microalgal biofuels remains impracticable due to the lack of suitable industrial strains with high growth rate and lipid productivity. Engineering of metabolic pathways is a potential strategy for the improvement of microalgal strains for the production of lipids and also value-added products in microalgae. Malonyl CoA-acyl carrier protein transacylase (MCAT) has been reported to be involved in fatty acid biosynthesis. Here, we identified a putative MCAT in the oleaginous marine microalga Nannochloropsis oceanica. NoMCAT overexpressing N. oceanica showed a higher growth rate and photosynthetic efficiency. The neutral lipid content of engineered lines showed a significant increase by up to 31% compared to wild type. Gas chromatography-mass spectrometry analysis revealed that NoMCAT overexpression significantly altered the fatty acid composition. The composition of eicosapentaenoic acid (C20:5), which is a polyunsaturated fatty acid necessary for animal nutrition, increased by 8%. These results demonstrate the role of MCAT in enhancing fatty acid biosynthesis and growth in microalgae, and also provide an insight into metabolic engineering of microalgae with high industrial potential. [ABSTRACT FROM AUTHOR]

We investigated the toxicity of Karenia mikimotoi toward three model grazers, the cladoceran Moina mongolica, the copepod Pseudodiaptomus annandalei, and the crustacean Artemia salina, and explored its chemical response upon zooplankton grazing. An induction experiment, where K. mikimotoi was exposed to grazers or waterborne cues from the mixed cultures revealed that K. mikimotoi might be toxic or nutritionally inadequate toward the three grazers. In general, direct exposure to the three grazers induced the production of hemolytic toxins and the synthesis of eicosapentaenoic acid ( EPA). Both EPA and the hemolytic toxins from K. mikimotoi decreased the survival rate of the three grazers. In addition, the survival rates of M. mongolica, P. annandalei, and A. salina in the presence of induced K. mikimotoi that had previously been exposed to a certain grazer were lower than their counterparts caused by fresh K. mikimotoi, suggesting that exposure to some grazers might increase the toxicity of K. mikimotoi. The chemical response and associated increased resistance to further grazing suggested that K. mikimotoi could produce deterrents to protect against grazing by zooplankton and that the substances responsible might be hemolytic toxins and EPA. [ABSTRACT FROM AUTHOR]

Phosphorus is an important macronutrient. To understand the molecular and cellular responses to phosphorus stress better, transcriptome profiling in combination with biochemical investigations was conducted in the model diatom P haeodactylum tricornutum. Out of 10 402 predicted genes, 2491 and 405 genes were significantly upregulated or downregulated respectively. Unsurprisingly, genes associated with phosphate uptake were upregulated, such as the phosphate transporters and alkaline phosphatases. Genes encoding stress-shock proteins were accordingly upregulated, including genes associated with stress-responsive proteins, signal transduction and secondary metabolism. Additionally, genes related to protein translation, carbon fixation, glycolysis and the citric acid cycle were also upregulated. Genes associated with gene transcription were downregulated, thereby resulting in the upregulation of translation to compensate for the limited supply of messenger RNA. The downregulation of genes related to β-oxidation could contribute to the accumulation of fatty acids. Accordingly, triacylglycerols, which are important for energy storage, were determined to increase by 1.65-fold. Intracellular membranes, other than chloroplast membranes, tended to be dispersed; this finding was in accordance with the increased transcription of a total of 11 genes encoding putative phospholipases. Taken together, this work revealed the coordination of multiple metabolic pathways and certain key genes in the adaptation of P . tricornutum to phosphorus stress. [ABSTRACT FROM AUTHOR]

The effects of five natural products on the growth of three harmful algae species including Chattonella marina Hara et Chihara, Alexandrium tamarense Balech and Karenia mikimotoi ( Miyake & Kominami ex Oda) G. Hansen & Ø. Moestrup were observed. Four products including ε-polylysine, betaine, stachydrine and berberine exhibited selectively inhibitory effects against the three algae. However, the other product chitosan had no obvious inhibition against the above algae. Berberine and ε-polylysine exhibited relatively higher inhibitory capability against C. marina, and betaine had the highest inhibitory effect against A. tamarense. While only berberine could effectively inhibit the growth of K. mikimotoi with LC50, 120 at 3.1 mg/L. The fast inhibitory effect against K. mikimotoi and environmental safety of berberine suggested that it might be a potential algaecide against K. mikimotoi. [ABSTRACT FROM AUTHOR]

The marine diatom Phaeodactylum tricornutum, a widely used forage species, has a storage lipid content of up to 30% dry cell weight. To explore the mechanism behind the high storage lipid accumulation in this diatom, acetyl-CoA carboxylase (ACCase), which catalyzes the first committed step of the fatty acid biosynthetic pathway, was characterized in this study. A homogeneous type of ACCase ( PtACC) was identified from P. tricornutum by homology searches. The first exon of the ACCase gene ( PtACC-1) was cloned. PtACC-1 was fused with a Myc epitope tag and cloned into plasmid pMD18 driven by the LacZ promoter and expressed in Escherichia coli. The expression of the PtACC-1-Myc protein was verified by Western blot. The neutral lipid content in transformed E. coli increased substantially by twofold as determined by Nile red fluorescent dye staining. Concomitantly, ACCase activity increased by 1.72-fold. The fatty acid composition, analyzed by GC-MS, demonstrated a significant difference in the ratio of saturated fatty acids and monounsaturated fatty acids (MUFAs). MUFAs of PtACC-1 expressing cells increased by 13%. This study represents the first characterization of the key domains of ACCase from a diatom and demonstrates high neutral lipid accumulation in E. coli expressing PtACC-1, providing an additional genetic resource with the potential for biodiesel development. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bacterial leaf blight and leaf streak are the two most damaging bacterial diseases of rice. However, few bactericidal chemicals are available for controlling both diseases. The antibacterial properties of two kinds of chitosan with different molecular weights and degrees of N-deacetylation and their effect on rice bacterial leaf blight and leaf streak were evaluated. RESULTS: Results showed that the two kinds of chitosan solution possess a strong antibacterial activity against both rice bacterial pathogens and significantly reduced disease incidence and severity by comparison with the control under greenhouse conditions. However, the interaction between chitosan and rice pathogens was affected by the type and concentration of chitosan, the bacterial species and the contact time between chitosan and bacteria. The direct antibacterial activity of chitosan may be attributed to both membrane lysis and the destruction of biofilm. In addition, both chitosan solutions significantly increased the activities of phenylalanine ammonia lyase, peroxidase and polyphenol oxidase in rice seedlings following inoculation of two rice pathogens by comparison with the control. CONCLUSION: The role of chitosan in protection of rice against bacterial pathogens has been shown to involve direct antibacterial activity and indirect induced resistance. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Shoot and branch canker and tree decline of kumquat ( Fortunella margarita cv. Guban) were recorded in Yangshuo County, Guilin City, in the Guangxi Zhuang Autonomous Region of China during 2008-2011. Fusarium oxysporum and a new Fusarium species within the Gibberella fujikuroi complex ( Fusarium sp. GLB1) were isolated repeatedly from the infected shoots and branches. Species identifications were verified by their high translation elongation factor 1-alpha ( TEF1) sequence similarity with those of the species epitypes. Koch's postulates were fulfilled on kumquat (cv. Guban) and mandarin establishing pathogenicity. To our knowledge, this is the first report of Fusarium shoot canker disease caused by F. oxysporum and Fusarium sp. on kumquat. [ABSTRACT FROM AUTHOR]

• Arabidopsis thaliana acyl-CoA-binding protein 2 (ACBP2) was observed to interact with farnesylated protein 6 (AtFP6), which has a metal-binding motif (M/LXCXXC). Their interaction and expression in response to heavy metals were investigated. • Yeast two-hybrid analysis and in vitro assays showed that an ACBP2 derivative lacking ankyrin repeats did not interact with AtFP6, indicating that the ankyrin repeats mediate protein–protein interaction. Autofluorescence-tagged ACBP2 and AtFP6 transiently co-expressed in tobacco ( Nicotiana tabacum) were both targeted to the plasma membrane. • Reverse transcriptase polymerase chain reaction and northern blot analyses revealed that AtFP6 mRNA was induced by cadmium (Cd(II)) in A. thaliana roots. Assays using metal-chelate affinity chromatography demonstrated that in vitro translated ACBP2 and AtFP6 bound lead (Pb(II)), Cd(II) and copper (Cu(II)). Consistently, assays using fluorescence analysis confirmed that (His)6-AtFP6 bound Pb(II), like (His)6-ACBP2. • Arabidopsis thaliana plants overexpressing ACBP2 or AtFP6 were more tolerant to Cd(II) than wild-type plants. Plasma membrane-localized ACBP2 and AtFP6 probably mediate Pb(II), Cd(II) and Cu(II) transport in A. thaliana roots. Also, (His)6-ACBP2 binds [14C]linoleoyl-CoA and [14C]linolenoyl-CoA, the precursors for phospholipid repair following lipid peroxidation under heavy metal stress at the plasma membrane. ACBP2-overexpressing plants were more tolerant to hydrogen peroxide than wild-type plants, further supporting a role for ACBP2 in post-stress membrane repair. [ABSTRACT FROM AUTHOR]

Hepatitis B virus X protein (HBx) plays a crucial role in the development of hepatocellular carcinoma (HCC). However, the significance of circulating antibody to hepatitis B virus X antigen (anti-HBx) in sera remains unclear. In the present study, we examined the titers of anti-HBx (IgG) in the sera from 173 patients with chronic hepatitis B (CHB), 106 liver cirrhosis (LC), and 61 HCC by enzyme-linked immunosorbent assay (ELISA), respectively. Our data showed that the positive rates of anti-HBx were higher in sera of LC (40.6%) and HCC (34.4%) than those of CHB (10.4%), P < .05. In all 40 patients with anti-HBx+ out of 340 patients, 39 (97.5%) were HBsAg/HBeAg/anti-HBc+ and 1 (2.5%) was anti-HBs+ (P < .01), suggesting that anti-HBx in sera is a marker of HBV replication rather than a protective antibody. Thus, our findings reveal that circulating anti-HBx in sera is one of the markers of development of LC and HCC mediated by HBV. [ABSTRACT FROM AUTHOR]

Prevacuolar compartments (PVCs) and endosomal compartments are membrane-bound organelles mediating protein traffic to vacuoles in the secretory and endocytic pathways of plant cells. Over the years, great progress has been made towards our understanding in these two compartments in plant cells. In this review, we will summarize our contributions toward the identification and characterization of plant prevacuolar and endosomal compartments. Our studies will serve as important steps in future molecular characterization of PVC biogenesis and PVC-mediated protein trafficking in plant cells. [ABSTRACT FROM AUTHOR]