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Fungal pathogen contamination is one of the most important factors affecting the postharvest quality and shelf life of wolfberry fruits. Therefore, the prevention and control of fungal pathogens that cause fruit rot has become particularly important. Volatile antifungal agents of biological origin have broad application prospects. They may be safer and more efficient than traditional physical and chemical methods. Four pathogenic fungi were isolated and purified from rotting wolfberry. These pathogenic fungi were determined to be Mucor circinelloides LB1, Fusarium arcuatisporum LB5, Alternaria iridiaustralis LB7, and Colletotrichum fioriniae LB8. In vitro fumigation experiments showed that 2,3-butanedione can effectively inhibit the mycelial growth, spore germination, and sporulation ability of pathogenic fungi. The scanning electron microscope (SEM) showed morphological changes in hyphae. Propidium iodide (PI) Staining and leakage of 260 and 280 nm-absorbing increased, suggesting damage to cell membranes. Furthermore, 2,3-butanedione was found to significantly improve fruit firmness, soluble solid, total phenol, flavonoid, and soluble sugar content, as well as higher SOD enzyme activity and lower PPO and POD enzyme activity in the treated fruit, indicating that 2,3-butanedione can effectively reduce the adverse effects of pathogenic fungi in wolfberry. Based on these results, we conclude that 2,3-butanedione is effective against infection by pathogenic fungi in post-harvest wolfberry. 2,3-butanedione should be considered a viable substitute for conventional fungicides that are currently used to control rot in wolfberry., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ling, Luo, Zhao, Yang, Cheng and Pang.)

Aims: Electroactive micro-organisms play a significant role in microbial fuel cells. It is necessary to discover potential resources in plant endophytes. In this study, plant tissues were selected to isolate endophytic bacteria, and the electrochemical activity potential was evaluated., Methods and Results: The microbial fuel cell (MFC) is used to evaluate the electricity-producing activity of endophytic bacteria in plant tissues, and the species distribution of micro-organisms in the anode of the MFC after inoculation of plant tissues is determined by high-throughput sequencing. Twenty-six strains of bacteria were isolated from plant tissues belonging to Angelica and Sweet Potato, of which 17 strains from six genera had electrochemical activity, including Bacillus sp., Pleomorphomonas sp., Rahnella sp., Shinella sp., Paenibacillus sp. and Staphylococcus sp. Moreover, the electricity-producing micro-organisms in the plant tissue are enriched. Pseudomonas and Clostridioides are the dominant genera of MFC anode inoculated with angelica tissue. Staphylococcus and Lachnoclostridium are the dominant genera in MFC anode inoculated with sweet potato tissue. And the most representative Gram-positive strain Staphylococcus succinus subsp. succinus H6 and plant tissue were further analysed for electrochemical activity. And a strain numbered H6 and plant tissue had a good electrogenerating activity., Conclusion: This study is of great significance for expanding the resource pool of electricity-producing micro-organisms and tapping the potential of plant endophytes for electricity-producing., Significance and Impact of Study: This is the first study to apply plant endophytes to MFC to explore the characteristics of electricity production. It is of great significance for exploring the diversity of plant endophytes and the relationship between electricity producing bacteria and plants., (© 2021 The Society for Applied Microbiology.)

Bacillus subtilis strain CL2 is antagonistic to wolfberry postharvest pathogenic fungi. In this study, we isolated and screened this strain for in vitro experiments. The result of the two-sealed-base-plates method revealed that volatile organic compounds (VOCs) emitted from the strain CL2 inhibited the hyphal growth of four pathogenic fungi Mucor circinelloides LB1, Fusarium arcuatisporum LB5, Alternaria iridiaustralis LB7, and Colletotrichum fioriniae LB8. After exposure to VOCs for 5 days, the hyphal growth of the pathogen C. fioriniae LB8 was inhibited by 73%. Scanning electron microscopy revealed that the VOCs produced by B. subtilis CL2 caused the mycelium morphology of the pathogenic fungi to deform, twist, fold, and shrink. In the in vivo experiments, we noticed that VOCs could significantly reduce the weight loss rate of wolfberry fruits caused by the pathogenic fungus M. circinelloides LB1 and that the decay incidence rate were caused by the pathogenic fungi F. arcuatisporum LB5, A. iridiaustralis LB7, and C. fioriniae LB8. On the basis of the headspace-gas chromatography-ion mobility spectrometry analysis, seven VOCs produced by strain CL2 were identified. Among them, 2,3-butanedione and 3-methylbutyric acid are the main antifungal active substances. This study investigated the antifungal properties of VOCs produced by the strain CL2 on postharvest pathogenic fungi isolated from wolfberry fruits both in vivo and in vitro, thereby providing the theoretical basis for its future applications., (© 2020 Wiley-VCH GmbH.)

Recent advancements in the research on endophytes isolated from plants and crops have greatly broadened its application in various fields. Endophytic bacteria and endophytic fungi are known to promote the growth of various plants. Besides, the secondary metabolites such as alcohol and xylitol secreted by the endophytic yeast also help their hosts to resist microbial invasion. This makes them a potential substitute for chemical-based control methods. Moreover, the plant hosts can also provide nutrients for the growth of endophytic yeasts. To achieve the symbiotic relationship, yeasts must colonize most parts of the plant tissues, including intercellular spaces, cytoplasm, stomata of seeds, roots, stems, leaves, and fruits as well. Conventionally, isolation of endophytic yeasts from different plant tissues and understanding their interior plants colonization mechanism have remainedkey strategies to exploit their key potentials. In this review, we will elaborate on the diversity, characteristics of colonization, and the factors that influence the distribution of endophytic yeasts. This review also lays a theoretical foundation for the application of endophytic yeasts in various industrial and agricultural practices.

Epithelial wound healing is an evolutionarily conserved process that requires coordination across a field of cells. Studies in many organisms have shown that cytosolic calcium levels rise within a field of cells around the wound and spread to neighboring cells, within seconds of wounding. Although calcium is a known potent second messenger and master regulator of wound-healing programs, it is unknown what initiates the rise of cytosolic calcium across the wound field. Here we use laser ablation, a commonly used technique for the precision removal of cells or subcellular components, as a tool to investigate mechanisms of calcium entry upon wounding. Despite its precise ablation capabilities, we find that this technique damages cells outside the primary wound via a laser-induced cavitation bubble, which forms and collapses within microseconds of ablation. This cavitation bubble damages the plasma membranes of cells it contacts, tens of microns away from the wound, allowing direct calcium entry from extracellular fluid into damaged cells. Approximately 45 s after this rapid influx of calcium, we observe a second influx of calcium that spreads to neighboring cells beyond the footprint of cavitation. The occurrence of this second, delayed calcium expansion event is predicted by wound size, indicating that a separate mechanism of calcium entry exists, corresponding to cell loss at the primary wound. Our research demonstrates that the damage profile of laser ablation is more similar to a crush injury than the precision removal of individual cells. The generation of membrane microtears upon ablation is consistent with studies in the field of optoporation, which investigate ablation-induced cellular permeability. We conclude that multiple types of damage, including microtears and cell loss, result in multiple mechanisms of calcium influx around epithelial wounds., (Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

Metformin, a biguanide widely used in the treatment of type II diabetes, clearly exhibits antineoplastic activity in experimental models and has been reported to reduce cancer incidence in diabetics. There are ongoing clinical trials to evaluate its antitumor properties, which may relate to its fundamental activity as an inhibitor of oxidative phosphorylation. Here, we show that serine withdrawal increases the antineoplastic effects of phenformin (a potent biguanide structurally related to metformin). Serine synthesis was not inhibited by biguanides. Instead, metabolic studies indicated a requirement for serine to allow cells to compensate for biguanide-induced decrease in oxidative phosphorylation by upregulating glycolysis. Furthermore, serine deprivation modified the impact of metformin on the relative abundance of metabolites within the citric acid cycle. In mice, a serine-deficient diet reduced serine levels in tumors and significantly enhanced the tumor growth-inhibitory actions of biguanide treatment. Our results define a dietary manipulation that can enhance the efficacy of biguanides as antineoplastic agents that target cancer cell energy metabolism., (©2014 American Association for Cancer Research.)

Objective: To identify global research trends in the use of acupuncture to treat cerebral infarction., Data Retrieval: We performed a bibliometric analysis of studies on the use of acupuncture to treat cerebral infarction published during 2002-2011, retrieved from Scopus, using the key words of acupuncture and cerebral infarction or ischemic stroke., Inclusion Criteria: peer-reviewed articles on the use of acupuncture to treat cerebral infarction indexed in Scopus and published between 2002 and 2011; types of publications were original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items., Exclusion Criteria: articles that required manual searching or telephone access; documents that were not published in the public domain; and corrected papers., Main Outcome Measures: (a) Annual publication output; (b) language of publication; (c) type of publication; (d) key words of publication; (e) publication by research field; (f) publication by journal; (g) publication by country and institution; (h) publication by author; (i) most-cited papers between 2002 and 2006; and (j) most-cited papers between 2007 and 2011., Results: A total of 160 publications on the use of acupuncture to treat cerebral infarction from 2002-2011 were retrieved from Scopus. The number of publications increased gradually over the 10-year study period; most were written in Chinese or English. Articles and reviews constituted the major types. The most frequent key word used was acupuncture. The most prolific journals in this area were Zhongguo Zhen Jiu and the Chinese Journal of Clinical Rehabilitation. Of the 160 publications retrieved, half came from Chinese authors and institutions. Tianjin University of Traditional Chinese Medicine was the most prolific research institute. Two papers were cited 30 times; they were published in 2002 and 2009, respectively., Conclusion: In the field of neuroscience, there is little literature on acupuncture for cerebral infarction. The most-cited papers were cited 30 times in the past 3 years. We believe that, with advances in the study of mechanisms in neurobiology, research on acupuncture will also advance and will become the concern of more scholars.

Epidemiologic and experimental evidence suggest that a subset of breast cancer is insulin responsive, but it is unclear whether safe and effective therapies that target the insulin receptor (IR), which is homologous to oncogenes of the tyrosine kinase class, can be developed. We demonstrate that both pharmacologic inhibition of IR family tyrosine kinase activity and insulin deficiency have anti-neoplastic activity in a model of insulin-responsive breast cancer. Unexpectedly, in contrast to insulin deficiency, pharmacologic IR family inhibition does not lead to significant hyperglycemia and is well tolerated. We show that pharmacokinetic factors explain the tolerability of receptor inhibition relative to insulin deficiency, as the small molecule receptor kinase inhibitor BMS-536924 does not accumulate in muscle at levels sufficient to block insulin-stimulated glucose uptake. Metformin, which lowers insulin levels only in settings of hyperinsulinemia, had minimal activity in this normoinsulinemic model. These findings highlight the importance of tissue-specific drug accumulation as a determinant of efficacy and toxicity of tyrosine kinase inhibitors and suggest that therapeutic targeting of the IR family for cancer treatment is practical.

Insulin regulates glucose uptake by normal tissues. Although there is evidence that certain cancers are growth-stimulated by insulin, the possibility that insulin influences tumor glucose uptake as assessed by ( 18) F-2-Fluoro-2-Deoxy-d-Glucose Positron Emission Tomography (FDG-PET) has not been studied in detail. We present a model of diet-induced hyperinsulinemia associated with increased insulin receptor activation in neoplastic tissue and with increased tumor FDG-PET image intensity. Metformin abolished the diet-induced increases in serum insulin level, tumor insulin receptor activation and tumor FDG uptake associated with the high energy diet but had no effect on these measurements in mice on a control diet. These findings provide the first functional imaging correlate of the well-known adverse effect of caloric excess on cancer outcome. They demonstrate that, for a subset of neoplasms, diet and insulin are variables that affect tumor FDG uptake and have implications for design of clinical trials of metformin as an antineoplastic agent.

PTEN loss of function enhances proliferation, but effects on cellular energy metabolism are less well characterized. We used an inducible PTEN expression vector in a PTEN-null glioma cell line to examine this issue. While proliferation of PTEN-positive cells was insensitive to increases in glucose concentration beyond 2.5mM, PTEN-null cells significantly increased proliferation with increasing glucose concentration across the normal physiologic range to approximately 10mM, coinciding with a shift to glycolysis and "glucose addiction". This demonstrates that the impact of loss of function of PTEN is modified by glucose concentration, and may be relevant to epidemiologic results linking hyperglycemia to cancer risk and cancer mortality., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)

Purpose: Numerous dietary factors elevate serum levels of insulin and insulin-like growth factor I (IGF-I), both potent prostate cancer mitogens. We tested whether varying dietary carbohydrate and fat, without energy restriction relative to comparison diets, would slow tumor growth and reduce serum insulin, IGF-I, and other molecular mediators of prostate cancer in a xenograft model., Experimental Design: Individually caged male severe combined immunodeficient mice (n = 130) were randomly assigned to one of three diets (described as percent total calories): very high-fat/no-carbohydrate ketogenic diet (NCKD: 83% fat, 0% carbohydrate, 17% protein), low-fat/high-carbohydrate diet (LFD: 12% fat, 71% carbohydrate, 17% protein), or high-fat/moderate-carbohydrate diet (MCD: 40% fat, 43% carbohydrate, 17% protein). Mice were fed to maintain similar average body weights among groups. Following a preliminary feeding period, mice were injected with 1 x 10(6) LNCaP cells (day 0) and sacrificed when tumors were >or=1,000 mm(3)., Results: Two days before tumor injection, median NCKD body weight was 2.4 g (10%) and 2.1 g (8%) greater than the LFD and MCD groups, respectively (P < 0.0001). Diet was significantly associated with overall survival (log-rank P = 0.004). Relative to MCD, survival was significantly prolonged for the LFD (hazard ratio, 0.49; 95% confidence interval, 0.29-0.79; P = 0.004) and NCKD groups (hazard ratio, 0.59; 95% confidence interval, 0.37-0.93; P = 0.02). Median serum insulin, IGF-I, IGF-I/IGF binding protein-1 ratio, and IGF-I/IGF binding protein-3 ratio were significantly reduced in NCKD relative to MCD mice. Phospho-AKT/total AKT ratio and pathways associated with antiapoptosis, inflammation, insulin resistance, and obesity were also significantly reduced in NCKD relative to MCD tumors., Conclusions: These results support further preclinical exploration of carbohydrate restriction in prostate cancer and possibly warrant pilot or feasibility testing in humans.

The hedgehog signalling inhibitor cyclopamine has been shown to induce growth inhibition and cell cycle arrest in prostate cancer cell lines, but the mechanism of action has not been clearly defined, and observations between laboratories have not always been consistent. We first observed that albumin can protect PC-3 prostate cancer cells from cyclopamine-induced growth inhibition, suggesting that cyclopamine binds to albumin, and that only free cyclopamine is active. We then conducted a phospho-site protein kinase screen to elucidate the mechanism of cyclopamine-induced growth inhibition. Treatment of PC-3 cells with 5 or 10 microM cyclopamine for 72h resulted in a decrease in cell viability of approximately 50% and approximately 75%, respectively. A phospho-site protein kinase screen showed that cyclopamine decreased levels of phospho-Thr(187)-p27 by 71%. This phospho-site on p27 positively regulates its ubiquitin degradation; therefore a decrease in phospho-Thr(187)-p27 should correlate with increased levels of p27. Consistent with this hypothesis, treatment of PC-3 cells with cyclopamine resulted in a approximately 3-fold increase in p27 protein levels. Cdk-2 phosphorylates Thr(187)-p27, and immunoblotting demonstrated that cyclopamine treatment of PC-3 cells reduces the expression of cdk-2. Furthermore, cyclopamine decreased the levels of phosphorylated (activated) Akt, which is known to increase p27 degradation via Skp-2-induced ubiquitination. The mechanism by which cyclopamine decreases phosphorylated Akt is currently under investigation, but it may involve our observed cyclopamine-induced reduction in IRS-1 and IGF-II expression. These results demonstrate novel molecular correlates of cyclopamine-induced growth inhibition of prostate cancer cells.

Objectives: Preclinical evaluation of the anti-neoplastic activity of an insulin-like growth factor I receptor (IGF-IR) kinase inhibitor in ovarian cancer., Methods: The OVCAR-3 and OVCAR-4 cell lines were investigated under serum-free tissue culture conditions. IGF-I and IGF-II production were evaluated by standard ELISA and immunohistochemistry. IGF-IR expression and protein levels were evaluated by Western blotting. Cytotoxicity assays were performed in triplicates using the Alamar colorimetric assay. Apoptosis was evaluated by flow cytometry and by Western blotting for PARP., Results: The OVCAR-3 and OVCAR-4 cell lines produce IGF-I and IGF-II, and express IGF-IR, detectable by Western blotting, supporting the existence of an autocrine loop. The existence of this loop justified studies of NVP-AEW541, a small molecular weight inhibitor of the IGF-IR kinase. We observed growth inhibition of the ovarian cancer cell lines, with IC50 between 5 and 15 microM. We also observed that NVP-AEW541 sensitized cells to cisplatin in vitro. Western blotting demonstrated that NVP-AEW541 induced apoptosis at the concentrations that were used in the cytotoxicity assays, and decreased the concentration of the phosphorylated AKT signaling protein downstream of the IGF-IR., Conclusions: IGF-IR is a potential new molecular target in ovarian cancer. The anti-neoplastic activity of NVP-AEW541 in ovarian cancer was observed at concentrations higher than those previously reported for multiple myeloma, suggesting the possibility that a portion of the observed anti-neoplastic activity could involve targets other than the IGF-IR. Experiments are being conducted to investigate the cytotoxicity profile in vivo and the clinical relevance of NVP-AEW541 in ovarian cancer treatment.

Overexpression of the ErbB2 receptor in one-third of human breast cancers contributes to the transformation of epithelial cells and predicts poor prognosis for breast cancer patients. We report that the overexpression of ErbB2 inhibits IGF-I-induced MAPK signaling. IGF-I-induced MAPK phosphorylation and MAPK kinase activity are reduced in ErbB2 overexpressing MCF-7/HER2-18 cells relative to control MCF-7/neo cells. In SKBR3/IGF-IR cells, reduction of ErbB2 by antisense methodology restores the IGF-I-induced MAPK activation. The inhibition of IGF-I-induced MAP kinase activation in ErbB2 overexpressing breast cancer cells is correlated with decreased IGF-I-induced Shc tyrosine-phosphorylation, leading to a decreased association of Grb2 with Shc and decreased Raf phosphorylation. However, IGF-I-induced tyrosine-phosphorylation of IGF-I receptor and IRS-I and AKT phosphorylation were unaffected by ErbB2 overexpression. Consistent with these results, we observed that the proportion of IGF-I-stimulated proliferation blocked by the MAPK inhibitor PD98059 fell from 82.6% in MCF-7/neo cells to 41.2% in MCF-7/HER2-18 cells. These data provide evidence for interplay between the IGF-IR and ErbB2 signaling pathways. They are consistent with the view that the IGF-IR mediated attenuation of trastuzumab-induced growth inhibition we recently described is dependent on IGF-I-induced PI3K signaling rather than IGF-I-induced MAPK signaling.