First Report of Neofusicoccum parvum Causing Seedpod Blight on Lotus (Nelumbo nucifera) in China.

Lotus (Nelumbo nucifera Gaertn.) is a widely cultivated plant in China, and the fruit lotus variety has a high economic value attributed to the exquisite flavor of its fresh seeds. During the summer of 2023, an unidentified blight was observed affecting lotus seedpods in Jiande City, Zhejiang province, with approximately 65% of seedpods impacted in a 130-hectare area. The initial symptoms included dark purple spots on the lotus seedpod surface, which gradually expanded over time. After 5 to 7 days, the entire seedpod turned black, withering, and rendering the lotus seeds inedible. To identify the causal agent, tissues from symptomatic seedpods were excised and disinfected in 75% ethanol for 60 s, and washed twice in sterile distilled water. The disinfected symptomatic tissues (5 × 5 mm) were plated on potato dextrose agar (PDA), incubated at 25 ℃, transferred hyphal tips to obtain pure isolates after 3 days. Fungal colonies exhibiting Botryosphaeriaceae morphology were isolated from 33% of the samples (n = 15). Pure cultures were grown on PDA for both morphological and molecular identification. The colonies displayed a white aerial mycelium, turning olivaceous grey after 7 days. Pycnidia were produced within 3 weeks on PDA with added sterilized healthy lotus seedpod pieces on the surface. Conidia were hyaline, unicellular, ellipsoidal, 12.65 to 20.72 × 3.92 to 9.38 µm in size (mean 16.67 × 6.24 µm, n = 100). To determine the fungal species, genomic DNA was extracted from one representative isolate (ZJUP1112-1), to amplify four gene loci through polymerase chain reactions (PCR): rDNA internal transcribed spacer (ITS) with primers ITS1/ITS4, rDNA large subunit (LSU) with LR0R/LR5, the translation elongation factor 1-alpha gene (tef1) with EF1-728F/EF1-986R, and ß-tubulin gene (tub2) with Bt2a/Bt2b. The PCR products were Sanger sequenced in Zhejiang Shangya biotechnology co., LTD, and the resulting sequences were assembled and deposited in GenBank (ITS: OR740546; LSU: OR740547; tef1: OR776996; tub2: OR776997). BLAST searches indicated the highest nucleotide sequence identity with the reference strains of Neofusicoccum parvum CMW 9081 (ITS: 98.8%, AY236943; LSU: 100%, AY928045; tef1: 99.6%, AY236888; tub2: 99.3%, AY236917). Multi-locus phylogenetic analyses revealed that isolate ZJUP1112-1 formed a highly supported clade with N. parvum. Pathogenicity tests were performed on healthy lotus seedpods using mycelial plugs (5 mm diameter) from actively growing colonies of ZJUP1112-1 that were placed onto the front and side of the seedpods (6 each). Controls received PDA plugs. Treated seedpods were wrapped with parafilm and incubated at 25 ℃ and the experiment was repeated three times. After 5 days, dark purple lesions were observed on the inoculated seedpods, whereas controls remained symptomless. The same isolate was recovered from the margin of resulting lesions and confirmed by morphology, thus fulfilling Koch's postulates. N. parvum is a polyphagous pathogen causing blights and fruit rot on multiple economically important fruit crops, such as cacao (Puig et al. 2019), walnut (Chen et al. 2019), pistachio (Lopez-Moral et al. 2020), chestnut (Seddaiu et al. 2021), blueberry (Spetik et al. 2023) and mango (Polizzi et al. 2022), among others. To the best of our knowledge, this is the first report of N. parvum causing seedpod blight on lotus seedpods in China, which contributes to a better understanding of the pathogens affecting this plant species in China.

First Report of Monosporascus cannonballus causing Root Rot and Vine Decline in Watermelon (Citrullus lanatus) in China.

In June 2023, a sudden outbreak root rot and vine decline symptoms was observed during a watermelon (Citrullus lanatus T.) variety demonstration trial located in Taizhou City, Zhejiang Province, China, with an incidence rate ranging from 75% to 100% and an affected area of nearly 2,000 square meters. The disease initially appeared with a rapid and alarming invasion of root rot and vine decline symptoms within watermelon plants. Affected plants exhibited rapid deterioration, showing symptoms of wilting, yellowing and eventual demise, predominantly during the pre-harvest stage. Notably, numerous black, spherical, erumpent perithecia were clearly visible on the watermelon's root epidermis, a characteristic trait of the disease. Symptomatic plant samples were rigorously disinfected with 75% ethanol, and plated on potato dextrose agar medium for incubation at 25°C, successfully isolate two potential strains. These isolates were inoculated in oatmeal agar and incubated in a 25℃ light incubator. After 30 days, mature perithecia, the same as those found on the watermelon's root epidermis, reached a diameter of 500 µm. Each perithecium contained several pear-shaped asci, 56 to 108.5 µm in length and 30.5 to 46.4 µm in width, typically holding 1, rarely 2 ascospores. These characteristics align precisely with the typical strains of Monosporascus cannonballus Pollack and Uecker (1974). Additionally, sequencing the internal transcribed spacer region of ribosomal DNA (ITS) gene (White et al., 1990), large subunit ribosomal RNA (LSU) gene (Rehner and Samuels 1995), and beta-tubulin (TUB) gene (Glass and Donaldson, 1995) were performed. BLAST analysis indicated the highest nucleotide sequence identity with M. cannonballus CBS 586.93 reference sequence (ITS: 100%, JQ771930; TUB: 98.99%, JQ907292). Representative sequences of isolate ZJUP0990-2 from these regions were deposited in GenBank (Accession No.: OR357656 for ITS; OR474500 for LSU; OR365762 for TUB). A multigene phylogenomic analysis (ITS-LSU-TUB) was undertaken to ascertain the exact phylogenetic position of M. cannonballus within the genus Monosporascus. The amalgamation of both morphological and molecular insights consistently reaffirmed the accurate classification of the causative agent as M. cannonballus. To validate the pathogenicity of M. cannonballus, a controlled greenhouse experiment was conducted using watermelon (cv. Nabite) as the subject. Mycelium fragments, harvested from the edge of the colony ZJUP0990-2, were inoculated into oat liquid medium and cultivated under dark conditions at a consistent temperature of 30°C for 7 days. After 20 days, the inoculated plants exhibited root rot and wilting, mirroring the symptoms observed during the field outbreak. In contrast, the control plants did not exhibit any signs of disease. M. cannonballus was successfully re-isolated from the symptomatic roots of the inoculated plants, satisfying Koch's postulates. This experiment was repeated three times. This pathogenic fungus has previously been documented as a menace to melons in various regions including Mexico (Chew-Madinaveitia et al., 2012) and Brazil (Sales et al., 2004), as well as watermelons in Brazil (Sales et al., 2010), northern Mexico (Gaytan-Mascorro et al., 2012), and Saudi Arabia (Karlatti et al., 1997). To our knowledge, this is the first reported presence of M. cannonballus on watermelons in China. This new disease poses a serious threat to watermelon production, potentially leading to severe economic losses and impacting food security.

Increasing FLAIR signal intensity in the postoperative cavity predicts progression in gross-total resected high-grade gliomas.

To evaluate the prognostic value of fluid-attenuated inversion recovery (FLAIR) signal intensity of postoperative cavity on progression free survival (PFS) and overall survival (OS) in patients with high-grade gliomas (HGG). This study retrospectively enrolled 45 consecutive HGG patients. These patients had chemoradiotherapy after gross-total resection of tumors. Quantitative analysis of the FLAIR signal intensity in postoperative cavity and background was made. We evaluated the threshold value, accuracy, sensitivity, specificity, and survival state with this technique. The patients who progressed and patients who did not progress were 33 and 12 cases separately. The ratio of postoperative cavity and background (C-B) on FLAIR sequence in patients who progressed was higher than that of patients who did not progress (P = 0.014). The PFS of the patients who progressed was shorter than that of patients who did not progress (P = 0.008). The area under ROC curve, threshold, sensitivity, specificity of C-B ratio for predicting tumor progression were 0.875, 62.3, 69.7, 0.84, and 0.50% respectively. The PFS of lower signal group was much longer than that of higher signal group (P = 0.004). The OS of the patients with higher signal was shorter than that of patients with lower signal (P = 0.034). The increase of gray value of FLAIR in postoperative cavity may be used as an imaging marker for predicting tumor progression.

Mechanistic and kinetic implications on the ORR on a Au(100) electrode: pH, temperature and H-D kinetic isotope effects.

pH, temperature and H-D kinetic isotope effects (KIEs) on the ORR on Au(100) have been examined systematically using a hanging meniscus rotating disk electrode system. We found that for the cases with pH > 7, the ORR mainly goes through a 4-electron reduction to OH(-) at E > pzc (potential of zero charge) without any pH and H-D KIEs. When the pH at the electrode/electrolyte interface (pH(s)) is below 7, O2 only reduces to H2O2, its activity increases with pH(s), and a H-D KIE of above 2 is observed in 0.1 M HClO4. According to the experimental results in acid solution, a mechanism with O2 + H(+) + e → HO(2,ad) as the rate determining step followed by decoupled electron and proton transfer steps is proposed. The high activation barrier for O-O bond breaking and the fast oxidation of H2O2 or HO2(-) to O2 render the ORR observable only at potentials negative of the equilibrium potential (Eeq) of the redox of H2O2/O2 in acidic media or of HO2(-)/O2 in an alkaline environment. The apparent activation energy (E(a,app)) for O2 reduction to H2O2 is ca. 35 ± 3 kJ mol(-1) and to OH(-) is 60 ± 6 kJ mol(-1), while the pre-exponential factor (A) for the former is ca. 3-6 orders of magnitude smaller than that of the latter. The lower activity for O2 reduction to H2O2 on Au(100) is attributed to the small pre-exponential factor.

Epidemiology of Nontuberculous Mycobacteria in Tuberculosis suspects, Southwest of China, 2017-2022.

Objectives: This study summarizes the epidemiological characteristics, species distribution, and drug sensitivity of clinical nontuberculous mycobacteria (NTM) isolates at the Public Health Clinical Center of Chengdu, China, from January 2017 to December 2022. Methods: We retrospectively analyzed data from patients with clinically isolated NTM strains. Chi-square analysis assessed the rate of Mycobacterium strain isolation over 6 years. Results: The number of samples tested for Mycobacterium tuberculosis (MTB) and/or NTM increased each year, while MTB detection decreased and NTM detection rose significantly each year (P=0.03). The average age of NTM patients was 51 ± 17.53 years, with a 14.1% HIV infection rate. The predominant isolates were Mycobacterium avium-intracellulare (MAC) and M. chelonae/M. abscessus, with 96.4% of cases being of Han ethnicity. Amikacin, moxifloxacin, and clarithromycin were effective against M. avium and M. intracellulare; linezolid, amikacin, and cefoxitin were effective against M. chelonae/M. abscessus. Over 90% of NTM cases originated from the respiratory tract. Conclusion: The NTM isolation rate in Southwest China has risen in recent years, primarily among elderly patients with a high HIV co-infection rate. The main NTM isolates were MAC and M. chelonae/M. abscessus. Amikacin, moxifloxacin, clarithromycin, and linezolid exhibited strong antibacterial activity against SGM, while amikacin and linezolid displayed relatively better antibacterial activity against RGM. The prevalence of NTM infection may be positively associated with regional economic development and health conditions.

[Source Analysis and Risk Assessment of Heavy Metals in Soil of County Scale Based on PMF Model].

This study explores the pollution characteristics, risks, and sources of heavy metals in small-scale areas. Rongcheng District, Jieyang City, Guangdong Province was considered as the study area and enrichment factor (EF), pollution load index (PLI), potential ecological risk index (RI), and US EPA health risk assessment model were used to evaluate its environmental risk. Moreover, the source apportionment of heavy metals was analyzed through correlation analysis, the characteristic of spatial distribution, and a PMF model. The results showed that the mean concentrations of ω(Cr), ω(Hg), ω(As), ω(Pb), ω(Ni), ω(Cd), ω(Cu), and ω(Zn) were 54.87, 0.25, 8.35, 56.00, 15.38, 0.35, 30.56, and 124.23 mg·kg-1, respectively. The mean concentrations of all elements exceeded the local soil background value. In terms of EF level, Cr, As, Pb, and Ni showed negligible accumulation; Zn and Cu showed minor accumulation; and Hg and Cd showed moderate accumulation. The mean value of the pollution load index was 2.37, with a severe pollution level, and the eight elements were in different pollution levels. In total, the study region suffered severe ecological risk, Hg and Cd presented strong ecological risk, and other elements presented slight ecological risk. The non-carcinogenic risks under the three exposure paths were within the acceptable level. The carcinogenic risks (CR) of adults and children were 9.81E-05 and 5.59E-04, respectively, and Cr and As were the main contributors of CR. The results showed that the four sources of heavy metals were transportation sources (37.02%), parent material sources (18.53%), atmospheric deposition sources (26.49%), and industrial sources (17.96%).

Biological characteristics of Cionus latefasciatus (Coleoptera: Curculionidae) and effects of temperature on its growth and development.

Cionus latefasciatus Voss (Coleoptera: Curculionidae) is one of the most important insect pests on Scrophularia ningpoensis Hemsl. (Scrophulariales: Scrophuhrhceae), which is a well-known traditional Chinese medicine plant in southeast China. The biological characteristics and effects of temperature on the growth and development of C. latefasciatus were studied in nature, in the greenhouse, and in the laboratory. In the area studied, 9-12 generations of this weevil occurred per year depending on climatic conditions. The overwintered adults migrated to the plant-seeding fields in the earlier days of March, and adults of the last generation began to overwinter in early October. Female adults lived for 50-75 d and male adults for 50-65 d at 28 degrees C. Adults fed on leaves, buds, tender stems, and flower stalks during the entire developmental phase of the plant. Female adults began to lay eggs 2-4 d after emergence and laid an average of 330-390 eggs per female at 28 degrees C. The eggs were usually laid on the surface of the leaves or into the leaves. The larvae have four instars judging from the width of the cephalic capsule of the larvae. The larvae fed on leaves and buds of the plant. Under constant temperatures (17, 20, 25, 28, and 30 degrees C) and fixed humidity (75%), the development periods from egg to adult emergence were 36.91, 29.25, 19.11, 17.26, and 15.36 d, respectively, and 346.31 degree-days, in total, above a lower threshold of 7.7 degrees C was required; the survival rates from egg to adult emergence were 49.1, 62.5, 72.0, 78.7, and 50.0%, respectively. Laboratory experiments showed that the optimum temperature for the development from egg to adult emergence was 28 degrees C.

One-pot synthesis of thermosensitive glycopolymers grafted gold nanoparticles and their lectin recognition.

Thermosensitive glucose-functionalized glycopolymers grafted gold nanoparticles (Glyco@GNPs) with good colloidal stability and thermosensitive in aqueous solution were fabricated by reversible addition-fragmentation chain transfer (RAFT) mediated one-pot synthesis. The formation of core-shell morphology with about a 60 nm gold core in diameter and a glycopolymer shell of about 80 nm in thickness was indicated by transmission electron microscopy (TEM). The recognition ability of the Glyco@GNPs toward lectin concannavalin A (Con A) was verified by ultraviolet-visible spectroscopy and dynamic light scattering (DLS). The good cytocompatibility of the glycopolymers and Glyco@GNPs was proven by MTT assay on L-929 cells. Glyco@GNPs could effectively inhibit hepatoma cells SMMC-7721 growth after recognizing Con A was also proved by MTT assay and flow cytometry assay.

Preparation of chitosan-polyaspartic acid-5-fluorouracil nanoparticles and its anti-carcinoma effect on tumor growth in nude mice.

AIM: To prepare chitosan-polyaspartic acid-5-fluorouracil (CTS-Pasp-5Fu) nanoparticles and investigate its anti-carcinoma effect and toxicity. METHODS: CTS-Pasp-5Fu nanoparticles were synthesized by ionic gelatification. Male BABL/c nude mice were injected with SGC-7901 gastric carcinoma cell line mass to establish a human gastric carcinoma model. They were randomly allocated into 4 groups: CTS-Pasp-5Fu (containing 5-Fu 1.25 mg/kg), 5-Fu (1.25 mg/kg), CTS-Pasp and normal saline groups. Tumor weight was measured and assay of colony forming unit-granulocyte and macrophage (CFU-GM) was performed. The structural change of cells and tissues was observed and the Bax and Bcl-2 genes were detected. RESULTS: Compared with normal saline, the inhibition rates of tumor growth for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.58%, 58.69% and 70.82%, respectively. The tumor inhibition rates for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.09%, 65.3% and 72.79%, respectively. There was a significant decrease in the number of CFU-GM formation and increase of total bilirubin, and alanine aminotransferase in the 5-Fu group, but no change in those of the other three groups. There was no change in white blood cell count and creatinine among the four groups. Pathological section of liver and nephridial tissues showed that the damage in the 5-Fu group was more severe than that in the CTS-Pasp-5Fu group. 5-Fu and CTS-Pasp-5Fu groups could both down-regulate the Bcl-2 expression and up-regulate the Bax expression to different extent, and the accommodate effect of CTS-Pasp-5Fu was more obvious than 5-Fu. CONCLUSION: The tumor inhibition rate of CTS-Pasp-5Fu nanoparticles is much higher than that of 5-Fu alone.