Characterization of fluorescent pseudomonads responsible for the yellowing of oyster mushroom (Pleurotus ostreatus)

Fluorescent pseudomonads isolated from different lesions on caps and/or stipes of cultivated Pleurotus ostreatus were identified as strains of Pseudomonas tolaasii or showed the White Line Assay (WLA) feature of P. ‘reactans’ or were WLA-negative fluorescent Pseudomonas spp. Pseudomonas tolaasii was consistently associated with brown-reddish blotches on P. ostreatus pseudo-tissues, and in the pathogenicity assays caused depressed dark brown lesions with deliquescence on Agaricus bisporus pseudo-tissues blocks and brown-reddish blotches and yellow discoloration on P. ostreatus sporocarps. Pseudomonas ‘reactans’ and the WLA-negative fluorescent Pseudomonas spp. were mostly associated with superficial yellow lesions on P. ostreatus sporocarps, and in pathogenicity assays caused light or dark brown discoloration, depending on the isolates, on A. bisporus pseudo-tissues blocks and the yellow discoloration of P. ostreatus sporocarps. The results of this study indicate that the aetiology of lesions on cultivated P. ostreatus involves a complex composed of interactions between P. tolaasii, P. ‘reactans’ and Pseudomonas spp., but that individually these bacteria cause different symptoms. This is the first report where the pathogenicity features of these pathogens has been clearly ascertained, and that has fully satisfied Koch’s postulates for the bacteria on the host mushroom. On the basis of virulence, biochemical and physiological characters, the isolates of P. ‘reactans’ and Pseudomonas spp. responsible for yellowing of oyster mushroom belong to several species of Pseudomonas

Bioactive and Structural Metabolites of Pseudomonas and Burkholderia Species Causal Agents of Cultivated Mushrooms Diseases1

Pseudomonas tolaasii, P. reactans and Burkholderia gladioli pv. agaricicola, are responsible of diseases on some species of cultivated mushrooms. The main bioactive metabolites produced by both Pseudomonas strains are the lipodepsipeptides (LDPs) tolaasin I and II and the so called White Line Inducing Principle (WLIP), respectively, LDPs which have been extensively studied for their role in the disease process and for their biological properties. In particular, their antimicrobial activity and the alteration of biological and model membranes (red blood cell and liposomes) was established. In the case of tolaasin I interaction with membranes was also related to the tridimensional structure in solution as determined by NMR combined with molecular dynamic calculation techniques. Recently, five news minor tolaasins, tolaasins A–E, were isolated from the culture filtrates of P. tolaasii and their chemical structure was determined by extensive use of NMR and MS spectroscopy. Furthermore, their antimicrobial activity was evaluated on target micro-organisms (fungi—including the cultivated mushrooms Agaricus bisporus, Lentinus edodes, and Pleurotus spp.—chromista, yeast and bacteria). The Gram positive bacteria resulted the most sensible and a significant structure-activity relationships was apparent. The isolation and structure determination of bioactive metabolites produced by B. gladioli pv. agaricicola are still in progress but preliminary results indicate their peptide nature. Furthermore, the exopolysaccharide (EPS) from the culture filtrates of B. gladioli pv. agaricicola, as well as the O-chain and lipid A, from the lipopolysaccharide (LPS) of the three bacteria, were isolated and the structures determined

Iacobellis

Summary. From superficial brown discolorations on the caps and stalks of deformed sporophores of Agaricus bisporus, bacteria were consistently isolated. On the basis of biochemical, nutritional and pathogenic characteristics, both on tissue blocks and on whole sporophores of A. bisporus, the above bacteria were identified as strains of Pseudomonas agarici

Response of traditional cultivars of Fagioli di Sarconi beans to artificial inoculation with common bacterial blight agents

Cultivars of the Fagioli di Sarconi are a pool of high value common bean (Phaseolus vulgaris L.) traditional cultivars selected from various landraces. These cultivars are protected by the European Union (Reg. CEE n° 1263/96) with the mark PGI (Protected Geographical Indication) and are cultivated in Basilicata (southern Italy) for the production of dry seeds. Fagioli di Sarconi cultivars are susceptible to common bacterial blight (CBB), a disease caused by the varieties fuscans and non-fuscans of Xanthomonas axonopodis pv. phaseoli. Five Fagioli di Sarconi cultivars (Tondino bianco, Verdolino, Cannellino, Tabacchino and Ciuoto) were artificially inoculated with two virulent strains of this bacterium, representative of 59 recently characterized strains of both the fuscans and non-fuscans varieties, with the aim to evaluate the susceptibility of these cultivars to the pathogens. Four CBB–resistant breeding–lines were used for comparison. Suspensions of the bacterium were injected into the first trifoliate leaflets of bean plants and produced typical CBB symptoms on the Fagioli di Sarconi cultivars, and hypersensitive necrotic lesions on the CBB–resistant breeding–lines. When cultivars were inoculated with the strain of the variety fuscans, Tondino bianco, Verdolino and Cannellino were more susceptible than Tabacchino and Ciuoto, whereas when they were inoculated with the non–fuscans strains, Tondino bianco, Tabacchino and Verdolino were more susceptible than Ciuoto and Cannellino. The tolerant cultivars appeared good candidates for the introgression of CBB–resistance characters in a breeding programme. The varying response of the traditional Fagioli di Sarconi bean cultivars to artificial inoculation suggests that several plant and pathogen factors are involved in the interaction between X. a. pv. phaseoli varieties and the bean cultivars

Response of traditional cultivars of Fagioli di Sarconi beans to artificial inoculation with common bacterial blight agents

Cultivars of the Fagioli di Sarconi are a pool of high value common bean (Phaseolus vulgaris L.) traditional cultivars selected from various landraces. These cultivars are protected by the European Union (Reg. CEE n° 1263/96) with the mark PGI (Protected Geographical Indication) and are cultivated in Basilicata (southern Italy) for the production of dry seeds. Fagioli di Sarconi cultivars are susceptible to common bacterial blight (CBB), a disease caused by the varieties fuscans and non-fuscans of Xanthomonas axonopodis pv. phaseoli. Five Fagioli di Sarconi cultivars (Tondino bianco, Verdolino, Cannellino, Tabacchino and Ciuoto) were artificially inoculated with two virulent strains of this bacterium, representative of 59 recently characterized strains of both the fuscans and non-fuscans varieties, with the aim to evaluate the susceptibility of these cultivars to the pathogens. Four CBB–resistant breeding–lines were used for comparison. Suspensions of the bacterium were injected into the first trifoliate leaflets of bean plants and produced typical CBB symptoms on the Fagioli di Sarconi cultivars, and hypersensitive necrotic lesions on the CBB–resistant breeding–lines. When cultivars were inoculated with the strain of the variety fuscans, Tondino bianco, Verdolino and Cannellino were more susceptible than Tabacchino and Ciuoto, whereas when they were inoculated with the non–fuscans strains, Tondino bianco, Tabacchino and Verdolino were more susceptible than Ciuoto and Cannellino. The tolerant cultivars appeared good candidates for the introgression of CBB–resistance characters in a breeding programme. The varying response of the traditional Fagioli di Sarconi bean cultivars to artificial inoculation suggests that several plant and pathogen factors are involved in the interaction between X. a. pv. phaseoli varieties and the bean cultivars

Retrospective Analysis of Clinical and Radiologic Data Regarding Zygomatic Implant Rehabilitation with a Long-Term Follow-Up

Background: Zygomatic implants have been introduced to rehabilitate edentulous patients with severely atrophic maxillae. Their use has been reported by several studies, describing high overall survival rates at medium-long follow-up. The aim of this study was to retrospectively analyze if a few patient-related and implant-related features are correlated with implant success or the onset of complications. Materials and methods: Data of patients treated with zygomatic implants between May 2005 and November 2012 at three private clinics were collected and retrospectively analyzed. For each implant, the following data were collected: implant length, insertion path, ridge atrophy and sinus characteristics (width, pneumatization, thickness of mucosae, patency of sinus ostium). General patient characteristics and health status data were also recorded. The outcomes evaluated were implant failure, infective complications, early neurologic complications and overall complications. Results: A total of 33 patients (14 men, 17 women, mean age 59.1) that received 67 zygomatic implants were included in the study. The mean duration of the follow-up was of 141.6 months (min 109; max 198). In this period, a total of 16 (23.88%) implants in 8 (24.24%) patients were removed and 17 (51.51%) patients with 36 (53.73%) implants reported complications. Immediate loading resulted in a significantly lower risk of complications compared with the two-stage prosthetic rehabilitation (OR: 0.04, p = 0.002). A thickness of the sinus mucosa > 3 mm emerged to be correlated with a greater occurrence of infective complications (OR: 3.39, p = 0.019). Severe and extreme pneumatization of the sinus was significantly correlated with the incidence of overall complications (p = 0.037) and implant failure (p = 0.044). A large sinus width was predisposed to a higher risk of neurologic complications, infective complications and implant failure (p = 0.036, p = 0.032, p = 0.04, respectively). Conclusions: zygomatic implants are an alternative procedure for atrophic ridge rehabilitation when a conventional implant placement is not possible. Several clinical and anatomical factors can have a significant role in complication occurrence

Potential Role of miR-196a and miR-196b as Prognostic Biomarkers of Survival in Head and Neck Squamous Cell Carcinoma: A Systematic Review, Meta-Analysis and Trial Sequential Analysis

The etiopathogenetic mechanisms involving tumor genesis, including alteration of cell proliferation, apoptosis, invasion, migration, and death, may lead to alterations in microRNAs (miR) expression. The hypothesis is that with the presence in the literature of recent studies conducted on miR-196a and miR-196b, it is possible to clearly determine, by aggregating the results, whether miR-196 upregulation in head and neck squamous cell carcinoma (HNSCC) tissues can represent a prognostic biomarker of survival through hazard ratio (HR) analysis. The systematic review was conducted following the indications of the PRISMA, and four electronic databases were used (Science Direct, SCOPUS, PubMed, and Cochrane Central), with the addition of gray literature. Combinations of keywords were used, such as miR-196, miR-196 AND HNSCC, microRNA AND HNSCC, LSCC AND miR-196, OSCC AND miR-196, OPSCC AND miR-196, HSCC AND miR-196. The meta-analysis and trial sequential analysis (TSA) were performed using RevMan 5.41 software and Stata 13 (StataCorp, College Station, TX, USA) with the implementation of the R 4.2 software. This search identified 1593 reports and, at the end of the selection, five articles were inserted. The results of the meta-analysis report an aggregate HR for overall survival (OS), between the highest and lowest miR-196 expression of 1.67, 95% CI: [1.16, 2.49]. In this meta-analysis, we found that the forest plot is in favor of higher OS in HNSCC patients, compared with the control, with low miR-196 expression, correlating this data with a favorable prognosis, which indicated the potential role of this miRNA in strengthening the therapy sensitiveness of the HNSCC patients. Consequently, the present systematic review places itself, together with other systematic reviews on this topic, in a key role to the finding of Phase 3 clinical trials studies, in search for a prognostic model of miR-196 for HNSCC. In conclusion, with the limitations of the meta-analysis, it can be argued that miRs of the miR-196 family could be independent prognostic biomarkers of survival for HNSCC

Biological Prognostic Value of miR-155 for Survival Outcome in Head and Neck Squamous Cell Carcinomas: Systematic Review, Meta-Analysis and Trial Sequential Analysis

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide; in fact, it is among the top six neoplasms, with an incidence of about 370,000 new cases per year. The 5-year survival rate, despite chemotherapy, radiotherapy, and surgery for stages 3 and 4 of the disease, is low. MicroRNAs (miRNAs) are a large group of small single-stranded non-coding endogenous RNAs, approximately 18–25 nucleotides in length, that play a significant role in the post-transcriptional regulation of genes. Recent studies investigated the tissue expression of miR-155 as a prognostic biomarker of survival in HNSCC. The purpose of this systematic review is, therefore, to investigate and summarize the current findings in the literature concerning the potential prognostic expression of tissue miR-155 in patients with HNSCC. The revision was performed according to PRISMA indications: three databases (PubMed, Scopus, and the Cochrane Register) were consulted through the use of keywords relevant to the revision topic. Totally, eight studies were included and meta-analyzed. The main results report for the aggregate HR values of 1.40 for OS, 1.36 for DFS, and 1.09 for DPS. Finally, a trial sequencing analysis was also conducted to test the robustness of the proposed meta-analysis

Is the Non-Coding RNA miR-195 a Biodynamic Marker in the Pathogenesis of Head and Neck Squamous Cell Carcinoma? A Prognostic Meta-Analysis

Head and neck squamous cell carcinoma (HNSCC) represents a heterogeneous group of neoplasms whose histological derivation comes from the mucous membranes lining the epithelium: the oral cavity, the larynx, the hypopharynx, the nasopharynx, and the oropharynx. The etiopathogenetic mechanisms involving tumor genesis including the alteration of cell proliferation, apoptosis, invasion, migration, and death may involve alterations in the expression of microRNA (miR). To date there have been no systematic reviews with meta-analysis conducted specifically on the role of miR-195 in HNSCC; therefore, our hypothesis was to evaluate if the aberrant expression of miR-195 in HNSCC tissues may represent a prognostic biomarker of survival through the hazard ratio (HR) and relative risk (RR) analysis. The systematic review was designed according to the PRISMA indications; in total, three electronic databases were consulted (PubMed, Scopus, Cochrane Central Trial) including Google Scholar and the gray literature, and a combination of keywords was used such as miR-195 AND HNSCC, microRNA AND HNSCC and miR-195. The meta-analysis and trial sequential analysis were performed using RevMan 5.41 software and TSA software (Cochrane Collaboration, Copenhagen, Denmark). This search identified 1592 articles and, at the end of the selection process, three articles were included. The results of the meta-analysis reported an aggregated risk ratio for overall survival (OS) between the expression of miR-195 at the highest and lowest of 0.36 and 6, respectively, 95% CI: [0.25, 0.51]. Heterogeneity was evaluated through Chi2 = 0.05 df = 2 (p = 0.98) and the Higgins index I2 = 0%. The test for the overall effect was Z = 5.77 (p < 0.00001). The forest plot was in favor of higher OS in patients with high miR-195 expression