R. La Rosa

HCV and HBV infection among multitransfused thalassemics from eastern sicily

SummarySerum specimens from 152 Sicilian multitransfused thalassemic subjects were tested for antibodies to hepatitis C virus (anti- HCV) and for HBV markers by enzyme linked immunoassay and with reference to anti-HCV, confirmed by recombinant immunoblot assay. A high rate (47%) of subjects was anti-HCV positive. HBsAg was found in 8% of patients and 55% had anti-HBs or anti-HBc antibodies or both. Contrary to HBV infection, anti-HCV seropositivity was related to the number of transfused units. The highest anti-HCV prevalence was observed between 16 and 20 years; 100% of persons older than 50 years had at least one marker of HBV infection. In conclusion, HCV and HBV are widespread among multitransfused thalassemics. Probably in our area, particularly during the pre-HBsAg screening era, several multitransfused patients were infected by HBV more readily than by HCV.ZusammenfassungDie Seren von 152 Thalassämie-Patienten, die häufig Bluttransfusionen erhalten hatten, wurden auf Antikörper gegen Hepatitis-C-Virus und HBV-Marker getestet. Ein hoher Prozentsatz (47%) erwies sich als anti-HCV positiv, was mit RIBA bestätigt wurde. HBsAg wurde bei 8% der Patienten gefunden und 55% hatten anti-HBc-oder Anti-HBs-Antikörper. Die dominierende anti-HCV-Prävalenz stand in Beziehung zur Transfusionshäufigkeit und war zwischen dem 16. und 20. Lebensjahr am höchsten. Im Gegensatz dazu stand die HBV-Infektion nicht im Verhältnis zu der Anzahl der Bluttransfusionen; bei 100% der Patienten über 50 Jahre wurde mindestens ein HBV-Infektionsmarker beobachtet. Bei Thalassämie-Patienten sind HCV- und HBV-Infektionen verbreitet. Wahrscheinlich haben sich vor dem Beginn des HBsAg-Screening in den Blutbanken viele Patienten mit dem HB-Virus infiziert.

CHARACTERIZATION OF ATYPICAL CLAVIBACTER MICHIGANENSIS subsp. MICHIGANENSIS POPULATIONS IN GREENHOUSE TOMATOES IN ITALY

SUMMARY The quarantine bacterium Clavibacter michiganensis subsp. michiganensis (Cmm) is the agent of tomato bacterial canker (TBC), one of the most destructive bacterial diseases of this crop, that causes severe economic losses worldwide. During a recent outbreak of TBC in Sicily (insular Italy), it was impossible to amplify the pat-1 gene by PCR with CMM5/CMM6 primers from affected greenhouse-grown plants from three farms, although Cmm-like colonies were consistently isolated. Microlog metabolic profile, 16S rDNA sequencing and the positive amplification of other Cmm DNA targets supported the identification of the strains as Cmm, suggesting the occurrence of a population lacking the virulence gene pat-1. A detailed phenotypic and molecular characterization of these Cmm strains and their virulence to tomatoes, as compared with Cmm reference strains is reported in this study. Pathogenicity tests revealed the strains under study were able to induce TBC, although delayed wilting symptoms were observed. Strains with or without pat-1 were undistinguishable, based on disease indexes.

HCV and HIV infection among intravenous drug abusers in eastern Sicily.

In a study of 175 intravenous drug addicts from Eastern Sicily, 58.3% were found to be anti-HCV positive. In this population, the presence of anti-HCV was independent of HIV infection, age, duration of drug use and the practice of needle sharing. This may indicate that HCV is more readily transmitted (or spread earlier in this population) among drug addicts than is HIV.

Bois noir phytoplasma variability in a Mediterranean vineyard system: new plant host and putative vectors

The presence of Bois noir phytoplasma (BNp, Stolbur, 16SrXII-A) in Sicily, one of the most important Italian grape-producing regions, has been known since 1996, but its epidemiology and distribution in the region have been studied only recently. Grapevines and weeds showing symptoms of phytoplasma infection were collected in an organic Chardonnay vineyard, chosen as model vineyard, and tested to verify BNp presence. Leaf- and plant-hoppers were also captured in the same field and included in the analysis. Plant and insect infections were assessed by nested PCR with universal and group-specific (16SrI and –V) phytoplasma primer pairs. BNp was detected in the weed species Erigeron bonariensis, which was then determined as a new natural host of this phytoplasma, and in several Auchenorrhyncha species besides Hyalesthes obsoletus, which can be regarded as new potential vectors. To further evaluate the genetic variability of BNp among host plants and potential vectors, PCR-RFLP of the Stolbur phytoplasma-specific vmp1 gene was carried out. The V1 profile was the most representative, other profiles (V4, V9, V10 and V11) were also detected.

Preliminary investigation on intrafamilial spread of hepatitis C virus (HCV)

To determine the risk of cohabitant HCV infection, we investigated the sera of 101 family members of 53 anti-HCV antibody positive chronic liver disease patients. Altogether 14.8% of the cohabitants were also anti-HCV antibody positive, compared to a prevalence of 1.4% in the general population. These results suggest that hepatitis-C-virus may spread by person-to-person infection.

HCV infection in HBsAg positive chronic liver disease.

The prevalence of anti-HCV antibodies was determined for a group of 68 patients with various forms of chronic liver disease. All patients that were anti-HCV positive but did not show signs of HBV replication had severe liver disease. We therefore suggest that HCV may be responsible for liver damage in HBsAg positive subjects when there are no evident signs of HBV replication.

Collecting and preserving plant DNA for huanglongbing diagnosis in citrus samples from China

Accurate and sensitive detection of Citrus Huanglongbing associated ‘Ca. Liberibacter’species, not currently reported in the European and Mediterranean area, is an imperative need to define certification programs, to prevent introduction of the bacteria and/or their vectors in the unaffected areas, and to delineate efficient management strategies in those areas where the disease has spread. In this study, we compared different citrus sample preparation procedures for PCR based detection methods of ‘Candidatus Liberibacter asiaticus’, in order to find out the best a way to transport and preserve samples of Shatangju mandarin and fingered citron obtained during a survey in citrus orchards in Guangdong in 2012. Results show that silica gel dehydrated midrib and bark citrus samples are amenable for DNA extraction and further processing by PCR and real-time PCR. FTA plant collecting card were useful for easily collect DNA samples in the field and processing by real-time PCR although at a lower concentration than extracted DNAs.

MIXED INFECTION OF PECTOBACTERIUM CAROTOVORUM subsp. CAROTOVORUM AND P. CAROTOVORUM subsp. BRASILIENSIS IN TOMATO STEM ROT IN ITALY

Grafted tomato plants grown in a soilless culture system in heated greenhouses in Sicily were affected by stem rot disease. Symptoms consisted of dark brown longitudinal discoloration of the basal part of the stem and petioles. Longitudinal sections of the stem revealed brown water-soaked or soft-rotted pith tissue and internal vascular discoloration. Bacterial isolates with two different colony morphologies were obtained from symptomatic tissues. Isolates were identified as Pectobacterium spp. on the basis of biochemical and molecular analyses. The analysis of the 16SrRNA gene sequence and of the concatenated sequences of the housekeeping genes rpoS and pgi revealed that the isolates of the two morphotypes belong to P. carotovorum subsp. carotovorum and P. c. subsp. brasiliensis, respectively. Isolates from both taxa reproduced disease symptoms on artificially inoculated tomato plants. This is the first report of P. carotovorum subsp. brasiliensis in Italy.

Survival of two biocontrol Pseudomonas strains in tomato fruits after inoculation at flowering through fruit ripening.

Pseudomonas syringae strain 1.1S and P. fluorescens strain A506 were applied to tomato plants to investigate their ability to survive during plant growth and ripening of fruits. Both strains were used to spray tomato flowers and green tomato fruits. Ripe tomato fruits were harvested and subjected to microbiological analysis. Peptone wash water and homogenates of fruit pulp were plated on selective media before and after enrichment. All tomatoes produced from inoculated flowers contained P. syringae on the surface of fruits (100% in enriched samples) as well as in the pulp homogenates (100% before and after enrichment). All tomatoes produced from inoculated green fruits contained P. syringae on the surface (38% and 100% in wash water and in enriched samples, respectively) as well as in the pulp homogenates (90% and 100% before and after enrichment, respectively). Of the P. fluorescens surface-positive tomatoes, 37% were from fruits receiving flower inoculation and 77% were from fruits receiving green fruit inoculation. P. fluorescens was harboured in higher percentages in pulp homogenates of tomatoes produced from treated flowers and green fruits (62% and 100%, respectively). Results suggest that antagonistic P. syringae and P. fluorescens strains survive in and on tomato fruits from the time of inoculation at flowering or at early stage of fruit development through fruit ripening. Tomato flower and green surfaces of fruits are possible sites at which Pseudomonas may attach and remain viable during fruit development.