First Report of Tobacco Leaf Tip Blight Caused by Alternaria gossypina in China.

Tobacco (Nicotiana tabacum L.) belongs to the family Solanaceae, an economically significant crop (Zhou et al. 2023). Twelve samples with leaf spots were collected in Keti Village, Changshun County, Zunyi City, Guizhou province, China in 2022. Twenty-five percent of the samples had dry lesions near the leaf tip which resulted leaf tip blight after development. Fungi were isolated by a previous method (Wei et al. 2022). Six Alternaria strains were obtained and preserved in the Fungal Herbarium of Yangtze University (YZU), Jingzhou, Hubei, China. Among them, one strain YZU 221477 showed distinct cultural characteristics out of five A. alternata strains, which was again determined by growing on potato dextrose agar (PDA) at 25°C for 7 days in dark to evaluate. The colonies (60 mm in diameter) were white cottony in the center surrounded by vinaceous purple. To examine the morphology, mycelia were inoculated onto potato carrot agar (PCA) at 22°C, following an 8 h light/16 h dark photoperiod (Simmons 2007). Conidia were obclavate or ovoid, normally 3-5 conidial units per chain, 20-38 × 10-16.5 µm, 3 to 5 transverse septa, beakless or a short beak (4-30 µm). The observation results were consistent with those of A. gossypina (Zhang 2003). Total genomic DNA was extracted using the CTAB method and seven gene regions including internal transcribed spacer of rDNA (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1 alpha (TEF1), RNA polymerase second largest subunit (RPB2), Alternaria major allergen gene (Alt a 1), endopolygalacturonase (EndoPG) and an anonymous gene region (OPA10-2) were amplified with ITS5/ITS4, gpd1/gpd2, EF1-728F/EF1-986R, RPB2-5F/RPB2-7cR, Alt-for/Alt-rev, PG3/PG2b and OPA10-2L/OPA10-2R primers, respectively. All sequences were deposited in GenBank (ITS: OR710806; GAPDH: PP057862; TEF1: PP158601; RPB2: PP057863; Alt a 1: PP057865; EndoPG: PP057861; OPA10-2: PP057864). Combining with relevant sequences retrieved from the NCBI database were used for the phylogenetic analysis. Maximum Likelihood (ML) tree was constructed with RAxML v.7.2.8 employing GTRCAT model using 1000 bootstrap (BS) replicates to assess statistical support. The results indicated that the present strain grouped with A. gossypina (type strain of CBS 104.32) supported with 73% bootstrap values, also having a support of 0.83 Bayesian posterior probabilities values. Based on morphology and molecular evidence, the strain YZU 221477 is identified as Alternaria gossypina. Pathogenicity was examined to fulfill Koch's postulates. Mycelial plugs (6 mm diameter) of the present strain and A. alternata cultivated on PDA were taken from the margin and inoculated onto viable tobacco leaves (Cultivar: Yunyan 87, n=3) growing forty days, while controls were inoculated with sterile PDA. The assay was conducted three times. The plants were maintained at 25°C with humidity levels over 85% in a greenhouse. Leaves were evaluated after 7 days, necrotic spots encircled by yellow halos were on both inoculums, except controls. Pathogen re-isolation confirmed that it was the same as inoculated fungus based on morphology. A. gossypina was firstly found on cotton (Hopkins 1931), late reported to induce disease on Minneola, Nopalea, Hibiscus, Citrus, Solanum and Ageratina. To our knowledge, this is the first report of A. gossypina causing tobacco leaf tip blight in China, and it also provides a basis for controlling of tobacco leaf tip blight.

Three new Penicillium species isolated from the tidal flats of China.

During a survey of culturable fungi in the coastal areas of China, three new species of Penicillium sect. Lanata-Divaricata were discovered and studied with a polyphasic taxonomic approach, and then named as P. donggangicum sp. nov. (ex-type AS3.15900T = LN5H1-4), P. hepuense sp. nov. (ex-type AS3.16039T = TT2-4X3, AS3.16040 = TT2-6X3) and P. jiaozhouwanicum sp. nov. (ex-type AS3.16038T = 0801H2-2, AS3.16207 = ZZ2-9-3). In morphology, P. donggangicum is unique in showing light yellow sclerotia and mycelium, sparse sporulation, restricted growth at 37 °C, irregular conidiophores, intercalary phialides and metulae, and pyriform to subspherical conidia. P. hepuense is distinguished by the fast growth on CYA and YES and slow growth on MEA at 25 °C, weak or absence of growth at 37 °C, biverticillate and monoverticillate penicilli, and ellipsoidal conidia. P. jiaozhouwanicum is characterized by abundant grayish-green conidia en masse and moderate growth at 37 °C, the appressed biverticillate penicilli and fusiform, smooth-walled conidia. These three novelties were further confirmed by the phylogenetic analyses based on either the combined BenA-CaM-Rpb2 or the individual BenA, CaM, Rpb2 and internal transcribed spacer (ITS) sequences.

Gleevec and Rapamycin Synergistically Reduce Cell Viability and Inhibit Proliferation and Angiogenic Function of Mouse Bone Marrow-Derived Endothelial Progenitor Cells.

OBJECTIVE: This study investigates the synergistic effects of Gleevec (imatinib) and rapamycin on the proliferative and angiogenic properties of mouse bone marrow-derived endothelial progenitor cells (EPCs). MATERIALS AND METHODS: EPCs were isolated from mouse bone marrow and treated with different concentrations of Gleevec or rapamycin individually or in combination. The cell viability and proliferation were examined using the MTT assay. An analysis of cell cycle and apoptosis was performed using flow cytometry. Formation of capillary-like tubes was examined in vitro, and the protein expression of cell differentiation markers was determined using Western blot analysis. RESULTS: Gleevec significantly reduced cell viability, cell proliferation, and induced cell apoptosis in EPCs. Rapamycin had similar effects on EPCs, but it did not induce cell apoptosis. The combination of Gleevec and rapamycin reduced the cell proliferation but increased cell apoptosis. Although rapamycin had no demonstratable effect on tube formation, the combined therapy of Gleevec and rapamycin significantly reduced tube formation when compared with Gleevec alone. Mechanistically, Gleevec, but not rapamycin, induced a significant elevation in caspase-3 activity in EPCs, and it attenuated the expression of the endothelial protein marker platelet-derived growth factor receptor α. Functionally, rapamycin, but not Gleevec, significantly enhanced the expression of endothelial differentiation marker proteins, while attenuating the expression of mammalian target of rapamycin signaling-related proteins. CONCLUSIONS: Gleevec and rapamycin synergistically suppress cell proliferation and tube formation of EPCs by inducing cell apoptosis and endothelial differentiation. Mechanistically, it is likely that rapamycin enhances the proapoptotic and antiangiogenic effects of Gleevec by promoting the endothelial differentiation of EPCs. Given that EPCs are involved in the pathogenesis of some cardiovascular diseases and critical to angiogenesis, pharmacological inhibition of EPC proliferation by combined Gleevec and rapamycin therapy may be a promising approach for suppressing cardiovascular disease pathologies associated with angiogenesis.

Expression of CD4+CD25+CD127Low regulatory T cells and cytokines in peripheral blood of patients with primary liver carcinoma.

Objective: To assess the clinical utility of the ratio of CD4+CD25+CD127low regulatory T cells (Tregs) in subjects at high risk of HCC, investigate the relationship between the percentage of Tregs and the expression of transforming growth factor (TGF)-ß1 and interleukin (IL)-10 in patients with hepatocellular carcinoma before and after treatment. Methods: Peripheral venous blood was collected from patients with liver cancer before and after treatment. The proportion of CD4+CD25+CD127low Tregs was detected by flow cytometry. The levels of TGF-ß1 and IL-10 in serum were detected by enzyme-linked immunosorbent assay, and were compared with healthy subjects as a control group. Results: The proportion of CD4+CD25+CD127low to CD4+T lymphocytes in patients with hepatocellular carcinoma was significantly higher than that in healthy controls (P<0.01). The proportion of CD4+CD25+CD127lowTregs, whose AUC of ROC curve was 0.917, could effectively separate the HCC patients from the healthy subjects with a diagnostic sensitivity of 90%, specificity of 80%. The proportion of CD4+CD25+CD127low to CD4+T lymphocytes and the levels of TGF-ß1 and IL-10 in patients with hepatocellular carcinoma after the operation and chemotherapy were significantly lower than those before treatment (P<0.05).The proportion of CD4+CD25+CD127lowTregs was positively correlated with the concentrations of TGF-ß1 and IL-10 before and after treatment of primary liver cancer (P<0.05). Conclusion: CD4+CD25+CD127lowTregs may be a significant predictor of HCC biopsy outcome and play an inhibitory role on effector T cells by regulating cytokines.

Evaluation of Preprocedural Laboratory Parameters as Predictors of Drug-Eluting Stent Restenosis in Coronary Chronic Total Occlusion Lesions.

This retrospective, single-center study assessed the prognostic value of several emerging inflammatory markers as predictors of in-stent restenosis (ISR) after drug-eluting stent implantation for coronary chronic total occlusion (CTO) lesions. Consecutive patients (n = 416) who underwent successful percutaneous coronary intervention (PCI) for documented CTO lesions and with follow-up angiography were enrolled. Preprocedural high-sensitivity C-reactive protein (hsCRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and red cell distribution width (RDW) were analyzed. At mean follow-up of 14.4 ± 3.3 months, ISR occurred in 72 patients. Compared with the non-ISR group, preprocedural hsCRP level, PLR, NLR, and RDW were significantly higher in the ISR group. The ISR group also had significantly greater proportions of patients with diabetes and smoking history, lower estimated glomerular filtration rate, higher low-density lipoprotein cholesterol (LDL-C) level and neutrophil count, longer stent length, and higher rate of severe dissection. In multivariate analysis, NLR (odds ratio [OR]: 3.110; 95% confidence interval [CI], 2.102-4.063; P < .001) and PLR (OR: 1.029; 95% CI, 1.016-1.143; P < .001) were independent predictors of ISR, along with LDL-C level and stent length. In conclusion, higher preprocedural NLR and PLR levels were independent risk factors for the development of ISR in patients who underwent PCI for CTO lesions.

Manipulation of KCNE2 expression modulates action potential duration and Ito and IK in rat and mouse ventricular myocytes.

In heterologous expression systems, KCNE2 has been demonstrated to interact with multiple α-subunits of voltage-dependent cation channels and modulate their functions. However, the physiological and pathological roles of KCNE2 in cardiomyocytes are poorly understood. The present study aimed to investigate the effects of bidirectional modulation of KCNE2 expression on action potential (AP) duration (APD) and voltage-dependent K(+) channels in cardiomyocytes. Adenoviral gene delivery and RNA interference were used to either increase or decrease KCNE2 expression in cultured neonatal and adult rat or neonatal mouse ventricular myocytes. Knockdown of KCNE2 prolonged APD in both neonatal and adult myocytes, whereas overexpression of KCNE2 shortened APD in neonatal but not adult myocytes. Consistent with the alterations in APD, KCNE2 knockdown decreased transient outward K(+) current (Ito) densities in neonatal and adult myocytes, whereas KCNE2 overexpression increased Ito densities in neonatal but not adult myocytes. Furthermore, KCNE2 knockdown accelerated the rates of Ito activation and inactivation, whereas KCNE2 overexpression slowed Ito gating kinetics in neonatal but not adult myocytes. Delayed rectifier K(+) current densities were remarkably affected by manipulation of KCNE2 expression in mouse but not rat cardiomyocytes. Simulation of the AP of a rat ventricular myocyte with a mathematical model showed that alterations in Ito densities and gating properties can result in similar APD alterations in KCNE2 overexpression and knockdown cells. In conclusion, endogenous KCNE2 in cardiomyocytes is important in maintaining cardiac electrical stability mainly by regulating Ito and APD. Perturbation of KCNE2 expression may predispose the heart to ventricular arrhythmia by prolonging APD.

Polydatin protects cardiac function against burn injury by inhibiting sarcoplasmic reticulum Ca2+ leak by reducing oxidative modification of ryanodine receptors.

Our recent studies demonstrate that burn trauma induces leaky sarcoplasmic reticulum (SR) in heart due to excessively active ryanodine receptor (RyR) function. SR Ca(2+) leak causes partial depletion of SR Ca(2+) content and disturbances in intracellular Ca(2+) homeostasis, resulting in the pathogenesis of burn-generated cardiac dysfunction. This study investigated the role of polydatin, a resveratrol glucoside, in preventing SR leak and its therapeutic effect against burn-generated cardiac dysfunction. We found that polydatin treatment improved cardiac function impaired by burn injury of 30% of total body surface area. Parallel to the alterations in cardiac function, polydatin significantly increased the defective systolic Ca(2+) transient and contractility in burn-traumatized cardiomyocytes. Burn injury increased the occurrence of Ca(2+) sparks. The enhancement of Ca(2+) spark-mediated SR leak caused partial depletion of SR Ca(2+) content in burn-traumatized cardiomyocytes. Furthermore, we found that the content of free thiols (the number of reduced cysteines) in RyR2 in cardiomyocytes determined by the monobromobimane fluorescence of RyR2 was decreased markedly in burn-traumatized hearts. Polydatin treatment decreased intracellular reactive oxygen species levels and restored the amount of free thiols in RyR2 in burns. Concomitantly, polydatin corrected Ca(2+) spark-mediated SR leak and restored SR Ca(2+) load. The systolic Ca(2+) transient and cellular contractility were significantly increased by polydatin treatment. Taken together, the present findings provide the first evidence demonstrating that polydatin prevents enhanced Ca(2+) spark-mediated SR leak by reducing oxidative stress in RyR2 in burn-traumatized heart, leading to protection of cardiac function against burn injury.