Characterization of a novel marine microbial uricase from Priestia flexa and evaluation of the effects of CMCS conjugation on its enzymatic properties.

A novel uricase producing marine bacterium Priestia flexa alkaAU was isolated and identified. The 16S rDNA and the uricase coding gene were sequenced, analyzed and submitted to GenBank. The uricase from Priestia flexa alkaAU (PFU) was purified, determined to be 58.87 kDa, and conjugated with carboxymethyl chitosan (CMCS) by ionic gelation. CMCS conjugation had no effect on the optimum pH of PFU but decreased the optimum temperature by 10 °C. CMCS conjugation increased the specific activity of PFU by 53% at the human body temperature (37 °C) and small intestine's pH (pH 6.8). Uricase thermostabilizing ability of CMCS was significant in the range of 37-80 °C but not at lower temperatures. For improvement of the pH stability of PFU, CMCS was more effective at pHs 3-5 than pHs 6-11. CMCS increased the half-life of PFU against artificial intestinal fluid by 1.5 folds, which demonstrated the potential capability of CMCS-PFU for oral administration.

Species Diversity and Toxigenic Potential of Fusarium incarnatum-equiseti Species Complex Isolates from Rice and Soybean in China.

Fusarium incarnatum-equiseti species complex (FIESC) strains are generally considered moderately virulent to many agricultural crops and produce a variety of mycotoxins, which represent a serious threat to food safety and public health. The occurrence of the FIESC strain in agricultural crops has been reported in various climatic regions, but detailed information on the species composition and toxigenic ability is rare in China. In this study, phylogenetic analyses were performed with combined sequences of EF-1a and RPB2 of 186 Fusarium isolates obtained from rice (Oryza sativa) and soybean (Glycine max). Twelve species were identified and 156 of the isolates were resolved within the Incarnatum clade of the FIESC species. Host influenced the population composition: rice isolates belonged to 12 species, among which FIESC 16, 18, and 24 strains were predominant; whereas five species were found among soybean isolates and FIESC 1, 16, and 18 strains dominated. Forty-three isolates were arbitrarily selected and analyzed for their Tri gene sequences and mycotoxigenic potential. Phylogenetic results based on the combined Tri5, Tri7, and Tri13 sequences were coincident with those from housekeeping markers. Type-A and -B trichothecenes were the main metabolites. Diacetoxyscirpenol was detected in all strains at varying concentrations. Nivalenol, 4-acetyl nivalenol, 3-acetyl deoxynivalenol, and neosolaniol were produced in members of the FIESC 1, 3, 7, 8, 15, 16, 17, and 18 strains. Our findings contribute valuable phylogenetic and toxigenic information necessary for the risk evaluation of mycotoxins in agricultural products.

Analysis of the Fusarium graminearum Species Complex from Gramineous Weeds Near Wheat Fields in Jiangsu Province, China.

Several weed species are known as alternative hosts of the Fusarium graminearum species complex (FGSC), and their epidemiological significance in Fusarium head blight (FHB) has been investigated; however, scant information is available regarding FGSC occurrence in weeds near Chinese wheat fields. To evaluate the potential role of gramineous weeds surrounding wheat fields in FHB, 306 FGSC isolates were obtained from 210 gramineous weed samples in 2018 in Jiangsu Province. Among them, 289 were Fusarium asiaticum, and the remainder were F. graminearum. Trichothecene genotype and mycotoxin analyses revealed that 74.3% of the F. asiaticum isolates were the 3-acetyldeoxynivalenol (3ADON) chemotype, and the remainder were the nivalenol (NIV) chemotype. Additionally, 82.4% of F. graminearum isolates were the 15-acetyldeoxynivalenol (15ADON) chemotype, and the remainder were the NIV chemotype. FHB severity and trichothecene analysis indicated that F. asiaticum isolates with the 3ADON chemotype were more aggressive than those with the NIV chemotype in wheat. 3ADON and NIV chemotypes of F. asiaticum isolated from weeds and wheat showed no significant differences in pathogenicity in wheat. All selected F. asiaticum isolates produced perithecia, with little difference between the 3ADON and NIV chemotypes. These results highlight the epidemiology of the FGSC isolated from weeds near wheat fields, with implications for reducing FHB inoculum in China.

Insight into the surfactin production of Bacillus velezensis B006 through metabolomics analysis.

Bacillus velezensis B006 is a biocontrol agent which functions through effective colonization and surfactin production. To reveal the surfactin-producing mechanism, gas chromatography-mass spectrometry based untargeted metabolomics was performed to compare the metabolite profiles of strain B006 grown in industrial media M3 and M4. Based on the statistical and pathway topology analyses, a total of 31 metabolites with a fold change of less than - 1.0 were screened as the significantly altered metabolites, which distributed in 15 metabolic pathways. Fourteen amino acids involving in the metabolisms of alanine/aspartate/glutamate, glycine/serine/threonine, arginine/proline, glutathione/cysteine/methionine and valine/leucine/isoleucine as well as succinic acid in TCA cycle were identified to be the hub metabolites. Aminoacyl-tRNA biosynthesis, glycerolipid metabolism, and pantothenate/CoA biosynthesis also contributed to surfactin production. To the best of our knowledge, this study is the first to investigate the metabolic pathways of B. velezensis on surfactin production, and will benefit the optimization of commercial fermentation for higher surfactin yield.

TUSC3 suppresses glioblastoma development by inhibiting Akt signaling.

Glioblastoma multiform is one of the most common and most aggressive brain tumors in humans. The molecular and cellular mechanisms responsible for the onset and progression of GBM are elusive and controversial. The function of tumor suppressor candidate 3 (TUSC3) has not been previously characterized in GBM. TUSC3 was originally identified as part of an enzyme complex involved in N-glycosylation of proteins, but was recently implicated as a potential tumor suppressor gene in a variety of cancer types. In this study, we demonstrated that the expression levels of TUSC3 were downregulated in both GBM tissues and cells, and also found that overexpression of TUSC3 inhibits GBM cell proliferation and invasion. In addition, the effects of increased levels of methylation on the TUSC3 promoter were responsible for decreased expression of TUSC3 in GBM. Finally, we determined that TUSC3 regulates proliferation and invasion of GBM cells by inhibiting the activity of the Akt signaling pathway.

Effect of Abiotic Conditions on Growth, Mycotoxin Production, and Gene Expression by Fusarium fujikuroi Species Complex Strains from Maize.

Fusarium fujikuroi species complex (FFSC) strains are a major concern for food quantity and quality due to their strong ability to synthesize mycotoxins. The effects of interacting conditions of water activity, temperature, and incubation time on the growth rate, toxin production, and expression level of biosynthetic genes were examined. High temperature and water availability increased fungal growth. Higher water activity was in favor of toxin accumulation. The maximum amounts of fusaric acid (FA) and fumonisin B1 (FB1) were usually observed at 20-25 °C. F. andiyazi could produce a higher content of moniliformin (MON) in the cool environment than F. fujikuroi. The expression profile of biosynthetic genes under environmental conditions varied wildly; it was suggested that these genes might be expressed in a strain-dependent manner. FB1 concentration was positively related to the expression of FUM1, while a similar correlation of FUB8 and FUB12 with FA production could be observed in F. andiyazi, F. fujikuroi, and F. subglutinans. This study provides useful information in the monitoring and prevention of such toxins entering the maize production chain.

Racial Context and Health Behaviors Among Black Immigrants.

Testing the Racial Context Hypothesis (Read and Emerson 2005), we examine the relationship between racial context of origin and three health behaviors (smoking, drinking, and physical activity) among Black immigrants in the USA. We conduct multinomial logistic regression analyses using data from the 2000-2018 National Health Interview Survey (N = 248,401) to determine if racial context of origin is a mechanism of health differential between Black immigrants and US-born Black Americans. Supporting the Racial Context Hypothesis, we find that Black immigrants from racially mixed (Mexico, Central America, the Caribbean, South America) and majority-Black contexts (Africa) are significantly less likely to be current or former smokers and drinkers than US-born Black Americans. Black immigrants from majority-white (Europe) contexts, on the other hand, look more similar to US-born Black Americans - again supporting the premise that racial context of origin is consequential for health. After controlling for a host of covariates, Black immigrants do not significantly differ from US-born Black Americans in exercise status. Together, these findings suggest that the impacts of racism and white supremacy have lasting effects on people of color, where Black immigrants from majority-white contexts exhibit worse health behaviors than their counterparts from majority-Black and racially mixed regions.

Psychological Distress among Black Immigrants by Region of Birth.

We assess the likelihood of moderate and severe psychological distress among Black immigrants. We test the region of context framework, which states that Black immigrants from majority-Black and racially mixed regions of origin have better health outcomes than Black immigrants from majority-white contexts. We utilize data from IPUMS Health Surveys, 2000-2018. We employed partial proportional odds models to assess the likelihood of moderate and severe psychological distress among Black immigrants and U.S.-born Black Americans. All immigrant groups, except for Black Europeans, are significantly less likely to be in moderate and severe distress vis-à-vis U.S.-born Black Americans (p < 0.01). Black Africans are about 54-58% less likely to be in severe distressed compared to U.S.-born Black Americans. Black immigrants from racially mixed and majority-Black contexts (Mexico, Central America, Caribbean, South America, and Africa) are significantly less likely to be afflicted with moderate and severe distress than U.S.-born Black Americans.

Draft genome sequence of a lipopeptide-producing Bacillus amyloliquefaciens strain isolated from wheat field soil with antagonistic activity against azole-resistant Fusarium graminearum.

OBJECTIVES: Lipopeptides have been revealed as good potential biocontrol agents against various pathogenic microbes. In the present work, we report the draft genome sequence of a lipopeptide-producing strain of Bacillus amyloliquefaciens (7D3) that showed good antifungal activity against the azole-resistant pathogenic fungus Fusarium graminearum. METHODS: Whole-genome sequencing of strain 7D3 was performed on an Illumina MiSeq 300 platform. Raw data were cleaned using Trim Galore v.0.4.0 and were checked for quality using FastQC. De novo assembly was performed using the SOAPdenovo2 package. Genes responsible for the biosynthesis of secondary metabolites were identified using antiSMASH. RESULTS: Bacillus amyloliquefaciens 7D3 genome assembly resulted in a total genome size of 3 913 220 bp with a G+C content of 46.13%. There were 3998 predicted genes with 72 tRNAs and 9 rRNAs. A total of ten gene clusters were found to be related to secondary metabolite biosynthesis, of which five were identified as lipopeptide synthesis clusters. CONCLUSION: This study presents the genome sequence of B. amyloliquefaciens 7D3, which exhibited intense antagonistic activity against azole-resistant fungi. The whole genome sequence will help in the search for novel antifungal peptides against drug-resistant pathogens.

Complete Genome Sequence of Achromobacter sp. Strain 77, a Hyphosphere Isolate of Fusarium oxysporum f. sp. cucumerinum.

The genome sequence of Achromobacter sp. strain 77, a bacterium isolated from the hyphosphere of Fusarium oxysporum f. sp. cucumerinum, is reported here. Genome sequencing and assembly yielded one chromosome consisting of 5,868,070 bases, with a G+C content of 65.89%.

Disproportionate impacts of COVID-19 on marginalized and minoritized early-career academic scientists.

Early research on the impact of COVID-19 on academic scientists suggests that disruptions to research, teaching, and daily work life are not experienced equally. However, this work has overwhelmingly focused on experiences of women and parents, with limited attention to the disproportionate impact on academic work by race, disability status, sexual identity, first-generation status, and academic career stage. Using a stratified random survey sample of early-career academics in four science disciplines (N = 3,277), we investigated socio-demographic and career stage differences in the effect of the COVID-19 pandemic along seven work outcomes: changes in four work areas (research progress, workload, concern about career advancement, support from mentors) and work disruptions due to three COVID-19 related life challenges (physical health, mental health, and caretaking). Our analyses examined patterns across career stages as well as separately for doctoral students and for postdocs/assistant professors. Overall, our results indicate that scientists from marginalized (i.e., devalued) and minoritized (i.e., underrepresented) groups across early career stages reported more negative work outcomes as a result of COVID-19. However, there were notable patterns of differences depending on the socio-demographic identities examined. Those with a physical or mental disability were negatively impacted on all seven work outcomes. Women, primary caregivers, underrepresented racial minorities, sexual minorities, and first-generation scholars reported more negative experiences across several outcomes such as increased disruptions due to physical health symptoms and additional caretaking compared to more privileged counterparts. Doctoral students reported more work disruptions from life challenges than other early-career scholars, especially those related to health problems, while assistant professors reported more negative changes in areas such as decreased research progress and increased workload. These findings suggest that the COVID-19 pandemic has disproportionately harmed work outcomes for minoritized and marginalized early-career scholars. Institutional interventions are required to address these inequalities in an effort to retain diverse cohorts in academic science.

[Simultaneous determination of 64 pesticide residues in shellfish by accelerated solvent extraction coupled with gas chromatography-tandem mass spectrometry].

A method was established for the determination of 64 pesticide residues in shellfish using accelerated solvent simultaneous extraction and purification coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). The target compounds were extracted from shellfish using 90% (v/v) acetonitrile aqueous solution with 60% of the pool volume at 85℃ via a single cycle of accelerated solvent extraction. The extracts were synchronously purified with primary secondary amine (PSA) and graphitized carbon black (GCB) added to the extracting cell. After concentration, the target compounds were detected by GC-MS/MS in the multiple reaction monitoring (MRM) mode, and quantified by using the external standard method. Under the optimized conditions, good linearities were obtained for the 64 pesticides in the range of 10.0-1000 µg/L, with coefficients of determination greater than 0.989. The limits of quantification for the method were between 2.0 µg/kg and 10.0 µg/kg. At four spiked levels (5.0, 10.0, 100 µg/kg, and the LOQ level) in clam, the recoveries of all the pesticides were between 69.4% and 129.7%, with the relative standard deviations varying from 0.7% to 16.0% (n=6). The method is simple, repeatable and sensitive, and it is suitable for the screening of various pesticide residues in shellfish products.

The transcription factor-encoding gene crtf is involved in Clonostachys chloroleuca mycoparasitism on Sclerotinia sclerotiorum.

Clonostachys chloroleuca 67-1 (formerly C. rosea 67-1) is a potential biocontrol fungus active against various fungal plant pathogens. From transcriptome sequencing of 67-1 parasitizing sclerotia of Sclerotinia sclerotiorum, we identified the transcription factor-encoding gene crtf that is significantly up-regulated during mycoparasitism. Transcription factors are widely distributed in fungi and involved in multiple biological processes. However, their role and regulatory mechanisms in mycoparasitism remain poorly understood. In this study, the function of crtf during 67-1 mycoparasitism was verified through gene knockout and complementation. The results showed that deletion of crtf did not influence fungal morphological characteristics, but the ability of the Δcrtf mutant to parasitize sclerotia and suppress soybean Sclerotinia white mold in the greenhouse was markedly diminished compared with the wild type strain. The biocontrol activity of Δcrtf recovered wild type levels when complemented with a plasmid expressing the crtf gene. These findings suggest that crtf plays a crucial role in C. chloroleuca mycoparasitism and provide insight into the molecular mechanisms underlying C. chloroleuca mycoparasitism on plant pathogenic fungi.

miR-422a Inhibits Glioma Proliferation and Invasion by Targeting IGF1 and IGF1R.

Glioma is a common type of malignant brain tumor characterized by aggressive metastasis capability. Recent evidence has suggested that noncoding RNAs, including microRNAs, have important functions in the pathophysiology of glioma development. In this study, we investigated the biological function of miR-422a in human glioma. We found that miR-422a was downregulated in glioma tissues. We also demonstrated that expression of miR-422a in glioma cells markedly suppressed cell proliferation, migration, and invasion. In addition, we identified insulin-like growth factor 1 (IGF1) and IGF1 receptor (IGF1R) as inhibitory targets of miR-422a in glioma cells. We established that the expression levels of miR-422a were negatively correlated with the expression levels of IGF1/IGF1R and the clinical parameters in glioma patients. An IGFR inhibitor, AG1024, completely blocked the activity of miR-442a on glioma cell proliferation and invasion, which further confirmed that miR-422a functions through IGF1 and IGF1R.

miRNA-214 Inhibits Cellular Proliferation and Migration in Glioma Cells Targeting Caspase 1 Involved in Pyroptosis.

Pyroptosis is a type of proinflammatory programmed cell death mediated by caspase 1 activity and occurs in several types of eukaryotic tumor cells, including gliomas. MicroRNAs (miRNAs), small endogenous noncoding RNAs, have been demonstrated to be advantageous in glioma therapy. However, the question of whether miRNAs regulate pyroptosis in glioma remains unknown. The current study found that caspase 1 expression was substantially increased in both glioma tissues and glioma cell lines, U87 and T98G, while miR-214 expression was significantly downregulated. Luciferase reporter assay recognized caspase 1 as a target gene of miR-214. These findings demonstrate that miR-214 could inhibit cell proliferation and migration through the regulation of pyroptosis intermediated by caspase 1 in glioma U87 and T98G cells and may suggest a novel therapeutic for the intervention of glioma.

[Repair of severe blepharoptosis with a frontalis muscle complex suspension technique].

OBJECTIVE: To search an ideal method for treatment of severe blepharoptosis. METHODS: Fifty-four eyes of 47 patients with severe blepharoptosis were undergoing for the treatment with a frontalis muscle complex flap, included in the frontalis muscle, orbicularis oculi muscle and SMAS membranes, to suspend the dropped eyelids. RESULTS: The 54 eyes with severe blepharoptosis were successfully treated with the frontalis muscle complex suspension technique. Although the lagophthalmos in different degrees was shown in 3 months after the operation, it usually disappeared 6 months after the operation. The results were shown good appearance without recurrence. CONCLUSION: The above mentioned technique may be a good and effective method for treatment of the severe blepharoptosis, compared with the traditional technique.