Detection of viable but non-culturable staphylococci in biofilms from central venous catheters negative on standard microbiological assays

Viable bacteria were sought in 44 Maki-negative biofilms from central venous catheters (CVCs) using epifluorescence microscopy after live/dead staining. Thirty (77%) samples contained viable but non-culturable (VBNC) cells; the majority were positive on real-time PCR specific for Staphylococcus epidermidis (one also for Staphylococcus aureus). Viable cells were significantly (p<0.01) associated with CVCs from febrile patients, three of whom showed S. epidermidis-positive blood cultures, suggesting that CVC-associated biofilms can be reservoirs for staphylococci in the VBNC state. The possible role of VBNC staphylococci in persistent infections related to medical devices requires further investigation.

First Report of Stemphylium vesicarium as Causal Agent of Wilting and Root Rotting of Radish Sprouts in Italy

A consistent contamination from a Stemphylium sp. was detected on radish (Raphanus sativus) seeds by a seed blotter test. Twenty-five percent of seed lots were contaminated. Stemphylium vesicarium (teleomorph Pleospora allii) was identified on the basis of morphological characters of conidia and conidiophores (4). Conidia were golden brown to dark drown, oblong to oval with one to four transverse and one to three longitudinal septa, constricted at one to three of the major transverse septa. Conidia dimensions ranged from 12 to 22 × 30 to 40 μm. Conidiophores were straight or occasionally one-branched with a swollen apex and one to four septate. Pseudothecia with asci and ascopores were observed on radish seeds. Asci were cylindrical to clavate with eight ascospores with up to six transverse septa and numerous longitudinal septa. Species identification was also confirmed after comparing the sequences of the internal transcribed spacer (ITS) region of rDNA and gpd (glyceraldehyde-3-phosphate dehydrogenase) (3) of four isolates with those of Stemphylium species already present in the NCBI database. Accessions Nos. AM 746020 to AM746023 and AM883174 to AM883177 were deposited for ITS and gpd, respectively. Artificial inoculations were carried out on radish seeds previously disinfected with 1% sodium hypochlorite for 10 min and then plated on S. vesicarium sporulating colonies grown on potato dextrose agar (PDA). The four sequenced isolates were tested for pathogenicity. Disinfected seeds were plated onto PDA only and used as a control. After 48 h of incubation, seeds were sown in sterilized soil in plastic plates. The emerging and the eventually dead plants were counted. Stem necrosis and root rotting developed on sprouts within the first week after sowing. On the surviving infected plantlets, wilting and death occurred on more than 70% of the plants within 4 weeks after sowing. Control plantlets obtained from disinfected seeds remained healthy. The fungus reisolated from wilted and dead plants was morphologically identical to the original isolates, thus confirming S. vesicarium as the causal agent. In Italy, this pathogen is common on asparagus (1), but it has also been reported on Allium spp., tomato, and pear. On European pear it is the causal agent of brown spot (2), a destructive disease in the Mediterranean area but also in the Netherlands and other continental European countries. On the basis of these results, seed contamination with S. vesicarium can represent a threat for the production of radish for sprout consumption. To our knowledge, this is the first report of S. vesicarium on radish plantlets in Italy. References: (1) F. Del Zan et al. L'informatore Agrario 11:95, 1989. (2) I. Llorente and E. Montesinos. Plant Dis. 90:1368, 2006. (3) B. M. Pryor and D. M. Bigelow. Mycologia 95:1141, 2003. (4) E. G. Simmons. Sydowia 38:284, 1985.

Cloning and characterization of a senescence inducing and class II tumor suppressor gene in ovarian carcinoma at chromosome region 6q27

Cytogenetic, molecular and functional analysis has shown that chromosome region 6q27 harbors a senescence inducing gene and a tumor suppressor gene involved in several solid and hematologic malignancies. We have cloned at 6q27 and characterized the RNASE6PL gene which belongs to a family of cytoplasmic RNases highly conserved from plants, to man. Analysis of 55 primary ovarian tumors and several ovarian tumor cell lines indicated that the RNASE6PL gene is not mutated in tumor tissues, but its expression is significantly reduced in 30% of primary ovarian tumors and in 75% of ovarian tumor cell lines. The promoter region of the gene was unaffected in tumors cell lines. Transfection of RNASE6PL cDNA into HEY4 and SG10G ovarian tumor cell lines suppressed tumorigenicity in nude mice. When tumors were induced by RNASE6PL-transfected cells, they completely lacked expression of RNASE6PL cDNA. Tumorigenicity was suppressed also in RNASE6PL-transfected pRPcT1/H6cl2T cells, derived from a human/mouse monochromosomic hybrid carrying a human chromosome 6 deleted at 6q27. Moreover, 63.6% of HEY4 clones and 42.8% of the clones of XP12ROSV, a Xeroderma pigmentosum SV40-immortalized cell line, transfected with RNASE6PL cDNA, developed a marked senescence process during in vitro growth. We therefore propose that RNASE6PL may be a candidate for the 6q27 senescence inducing and class II tumor suppressor gene in ovarian cancer.

The role of peroxisome proliferator-activated receptor gamma in bladder cancer in relation to angiogenesis and progression

Peroxisome proliferator-activated receptor gamma (PPAR gamma) immunohistochemical expression was analyzed in 75 human bladder tumor specimens, where the expression of some angiogenic factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived endothelial cell growth factor (PDECGF), and tumor progression markers, such as epidermal growth factor receptor (EGFr), p16, mutated p53, and normal pRB, were also analyzed. The results were then compared to the clinical and pathological characteristics of the disease. PPAR gamma was expressed more significantly in papillary tumors than in solid cancers, and its presence was associated with statistical significance to low incidence of tumor recurrence or progression. This significant association was observed also when PPAR gamma was expressed in the presence of PDECGF, which resulted, when considered alone, to an angiogenic factor typical of solid cancers and appeared related to poor prognosis. In the presence of bFGF, on the contrary, PPAR gamma expression no longer resulted to a significant association with low incidence of tumor recurrence or progression, suggesting a possible worsening role of this angiogenic factor, typical of papillary cancers, in its interaction with PPAR gamma.

Antiangiogenic, antitumoural and antimetastatic effects of two distamycin A derivatives with anti-HIV-1 Tat activity in a Kaposi's sarcoma-like murine model

The antiangiogenic, antitumoural and antimetastatic effects of two novel sulphonic derivatives of distamycin A, PNU145156E and PNU153429, were studied in a Kaposi's sarcoma-like tumour model obtained by injecting nude mice with cells releasing extracellular HIV-Tat protein, derived from a tumour which developed in a BK virus/tat transgenic mouse. Both PNU145156E and PNU153429 were administered intraperitoneally every fourth day for three weeks at doses of 100 or 50 mg/kg of body weight respectively, starting one day after injecting the tumour cells. Both drugs delayed tumour growth in nude mice, preventing neovascularization induced by the Tat protein. PNU153429 also significantly reduced the number and size of spontaneous tumour metastases. Both effects on tumour growth and metastases were augmented by treating simultaneously nude mice with 7.5 mg/kg of body weight of minocycline given per os daily for four weeks starting four days after injecting the tumour cells. Neither acute nor chronic toxic side-effects were observed during the life span of treated nude mice. Due to their antiangiogenic and anti-Tat effects, these drugs are promising for the treatment of Kaposi's sarcoma in AIDS patients.

Percutaneous vs. Totally implantable catheters in Home Parenteral Nutrition

The technique of the implementation of Home Parenteral Nutrition (HPN) is improving continuously so carrying minimum risk of technical complications and supplying maximum comfort for the patient. For example the HPN benefits of the recent availability of Ethil-Vinil-Acetate (EVA) bags that permit the contemporary administration of all nutrients, lipids included, and of infusion pumps which are lighter, safer and more versatile and which have rechargeable batteries. Some new types of completely implantable catheters with a subcutaneous reservoir present a better rationale compared with complications and with patient's compliance in respect of traditional percutaneous catheters used in HPN. We wanted to verify these presuppositions in a retrospective study with a completely implantable catheter, Port-A-Cath (PAC) Pharmacia, with a group of six patients already under HPN for a period of 901 patient-days with a percutaneous catheter. We compared the two methods of treatment after 1114 patient-days with the PAC. Concerning complications, we have three catheter related sepsis (3.3 1000 days) with percutaneous catheter and 1 sepsis (0.9 1000 days) with the PAC. We also had one catheter obstruction in a patient with the PAC implanted in the Inferior Vena Cava. All the patients accepted the new technique and even if they did not have the same motivation, all of them particularly appreciated the possibility of the avoidance of any external device. Our experience leads us to report that the Port-A-Cath system may be useful in long-term parenteral nutrition but other research is needed to confirm its rationale.