New Alien Plant Taxa for Italy and Europe: An Update

Despite the wide amount of scientific contributions published on alien plant species, their diffusion dynamics, and their interactions with native taxa, it is increasingly difficult to slow down their spreading and their negative impact on habitats. Last recent years, in fact, a sharp rise in the number of new alien plant taxa introduced in Italy and Europe has been recorded. The aim of this work is to investigate most of the Italian territory in order to verify whether this alarming trend is still underway. Specimen collections and/or observations of alien plants have been performed in as many as 12 Italian regions. All the collected specimens are stored in public or private herbaria. Taxa have been identified according to the literature from the countries of origin of the investigated taxa, while the nomenclature followed the current international references. Updates on 106 taxa are reported. In particular, among 117 new records, 89 are first records, 27 are changes to status and there is 1 extinction. Seven new taxa for Italian alien flora are reported, two of which are new to Europe. The administrative regions with the highest number of records are Calabria (48), Sardegna (17) and Sicilia (15). Five of the surveyed taxa, for the first time, have been considered invasive aliens to Italian territory. The unfrequent amount of original results provided by this work, over the simple importance of data itself, proves how floristic investigation, still today, represents one of the most effective tools in broadening the current knowledge about alien taxa and their dynamics.

Distinct structural variants and repeat landscape shape the genomes of the ancient grapes Aglianico and Falanghina

Mounting evidence recognizes structural variations (SVs) and repetitive DNA sequences as crucial players in shaping the existing grape phenotypic diversity at intra- and inter-species levels. To deepen our understanding on the abundance, diversity, and distribution of SVs and repetitive DNAs, including transposable elements (TEs) and tandemly repeated satellite DNA (satDNAs), we re-sequenced the genomes of the ancient grapes Aglianico and Falanghina. The analysis of large copy number variants (CNVs) detected candidate polymorphic genes that are involved in the enological features of these varieties. In a comparative analysis of Aglianico and Falanghina sequences with 21 publicly available genomes of cultivated grapes, we provided a genome-wide annotation of grape TEs at the lineage level. We disclosed that at least two main clusters of grape cultivars could be identified based on the TEs content. Multiple TEs families appeared either significantly enriched or depleted. In addition, in silico and cytological analyses provided evidence for a diverse chromosomal distribution of several satellite repeats between Aglianico, Falanghina, and other grapes. Overall, our data further improved our understanding of the intricate grape diversity held by two Italian traditional varieties, unveiling a pool of unique candidate genes never so far exploited in breeding for improved fruit quality.

Investigating the impact of pedoclimatic conditions on the oenological performance of two red cultivars grown throughout southern Italy

The cultivated grapevine, Vitis vinifera subsp. vinifera, possesses a rich biodiversity with numerous varieties. Each variety adapts differently to varying pedoclimatic conditions, which greatly influence the terroir expression of wine regions. These conditions impact vine growth, physiology, and berry composition, ultimately shaping the unique characteristics and typicity of the wines produced. Nowadays, the potential of the different adaptation capacities of grape varieties has not yet been thoroughly investigated. We addressed this issue by studying two grape varieties, Aglianico and Cabernet Sauvignon, in two different pedoclimatic conditions of Southern Italy. We evaluated and compared the effect of different pedoclimatic conditions on plant physiology, the microbial quality of grapes using Next-Generation Sequencing (NGS) technology, the expression trends of key genes in ripe berries and the concentration of phenolic compounds in grapes and wines by HPLC-MS, HPLC-DAD, NMR and spectrophotometric analyses. Metabolomic and microbiome data were integrated with quantitative gene expression analyses to examine varietal differences and plasticity of genes involved in important oenological pathways. The data collected showed that the phenotypic response of studied grapes in terms of vigor, production, and fruit quality is strongly influenced by the pedoclimatic conditions and, in particular, by soil physical properties. Furthermore, Aglianico grape variety was more influenced than the Cabernet Sauvignon by environmental conditions. In conclusion, the obtained findings not only reinforce the terroir concept and our comprehension of grape's ability to adapt to climate variations but can also have implications for the future usage of grape genetic resources.

Genetic diversity and signature of divergence in the genome of grapevine clones of Southern Italy varieties

Sexual reproduction has contributed to a significant degree of variability in cultivated grapevine populations. However, the additional influence of spontaneous somatic mutations has played a pivotal role in shaping the diverse landscape of grapevine agrobiodiversity. These naturally occurring selections, termed 'clones,' represent a vast reservoir of potentially valuable traits and alleles that hold promise for enhancing grape quality and bolstering plant resilience against environmental and biotic challenges. Despite their potential, many of these clones remain largely untapped.In light of this context, this study aims to delve into the population structure, genetic diversity, and distinctive genetic loci within a collection of 138 clones derived from six Campanian and Apulian grapevine varieties, known for their desirable attributes in viticulture and winemaking. Employing two reduced representation sequencing methods, we extracted Single-Nucleotide Polymorphism (SNP) markers. Population structure analysis and fixation index (FST) calculations were conducted both between populations and at individual loci. Notably, varieties originating from the same geographical region exhibited pronounced genetic similarity.The resulting SNP dataset facilitated the identification of approximately two hundred loci featuring divergent markers (FST ≥ 0.80) within annotated exons. Several of these loci exhibited associations with essential traits like phenotypic adaptability and environmental responsiveness, offering compelling opportunities for grapevine breeding initiatives. By shedding light on the genetic variability inherent in these treasured traditional grapevines, our study contributes to the broader understanding of their potential. Importantly, it underscores the urgency of preserving and characterizing these valuable genetic resources to safeguard their intra-varietal diversity and foster future advancements in grapevine cultivation.

Integrative analysis of metabolome and transcriptome profiles to highlight aroma determinants in Aglianico and Falanghina grape berries

BACKGROUND

The biochemical makeup of grape berries at harvest is essential for wine quality and depends on a fine transcriptional regulation occurring during berry development. In this study, we conducted a comprehensive survey of transcriptomic and metabolomic changes occurring in different berry tissues and developmental stages of the ancient grapes Aglianico and Falanghina to establish the patterns of the secondary metabolites contributing to their wine aroma and investigate the underlying transcriptional regulation.

RESULTS

Over two hundred genes related to aroma were found, of which 107 were differentially expressed in Aglianico and 99 in Falanghina. Similarly, 68 volatiles and 34 precursors were profiled in the same samples. Our results showed a large extent of transcriptomic and metabolomic changes at the level of isoprenoids (terpenes, norisoprenoids), green leaf volatiles (GLVs), and amino acid pathways, although the terpenoid metabolism was the most distinctive for Aglianico, and GLVs for Falanghina. Co-expression analysis that integrated metabolome and transcriptome data pinpointed 25 hub genes as points of biological interest in defining the metabolic patterns observed. Among them, three hub genes encoding for terpenes synthases (VvTPS26, VvTPS54, VvTPS68) in Aglianico and one for a GDP-L-galactose phosphorylase (VvGFP) in Falanghina were selected as potential active player underlying the aroma typicity of the two grapes.

CONCLUSION

Our data improve the understanding of the regulation of aroma-related biosynthetic pathways of Aglianico and Falanghina and provide valuable metabolomic and transcriptomic resources for future studies in these varieties.

Morphological and Genetic Clonal Diversity within the 'Greco Bianco' Grapevine (Vitis vinifera L.) Variety

Grapevine (Vitis vinifera L.) has been propagated vegetatively for hundreds of years. Therefore, plants tend to accumulate somatic mutations that can result in an intra-varietal diversity capable of generating distinct clones. Although it is common that winemakers request specific clones or selections for planting new vineyards, relatively limited information is available on the extent, degree, and morphological impact of the clonal diversity in traditional, highly valued grapevine varieties within production areas protected by geographical denomination of origin. Here, we present a morphological and genetic investigation of the intra-varietal diversity in 'Greco Bianco', the grapevine variety used to produce the DOCG and PDO "Greco di Tufo" wine. Seventeen clones from different farms (all within the allowed production area) were phenotypically characterized using ampelographic and ampelometric traits. The clones were also genotyped with Simple Sequence Repeats (SSR) and retrotransposon-based DNA markers (REMAP). The morphological analysis indicated a uniformity in the qualitatively scored traits, and a limited variability for the quantitative traits of the bunch and of the berry composition. The molecular markers also depicted variability among clones, which was more evident with the use of REMAPs. The comparison of the discriminatory information of the three analyses indicated that they provided different estimates of the level of diversity. The evaluation described herein of the clonal variability has implications for the management and protection of clonal selections in 'Greco Bianco' and prompts for further multidisciplinary investigations on its possible role in winemaking.

Aglianico Grape Seed Semi-Polar Extract Exerts Anticancer Effects by Modulating MDM2 Expression and Metabolic Pathways

Grapevine (Vitis vinifera L.) seeds are rich in polyphenols including proanthocyanidins, molecules with a variety of biological effects including anticancer action. We have previously reported that the grape seed semi-polar extract of Aglianico cultivar (AGS) was able to induce apoptosis and decrease cancer properties in different mesothelioma cell lines. Concomitantly, this extract resulted in enriched oligomeric proanthocyanidins which might be involved in determining the anticancer activity. Through transcriptomic and metabolomic analyses, we investigated in detail the anticancer pathway induced by AGS. Transcriptomics analysis and functional annotation allowed the identification of the relevant causative genes involved in the apoptotic induction following AGS treatment. Subsequent biological validation strengthened the hypothesis that MDM2 could be the molecular target of AGS and that it could act in both a p53-dependent and independent manner. Finally, AGS significantly inhibited tumor progression in a xenograft mouse model of mesothelioma, confirming also in vivo that MDM2 could act as molecular player responsible for the AGS antitumor effect. Our findings indicated that AGS, exerting a pro-apoptotic effect by hindering MDM2 pathway, could represent a novel source of anticancer molecules.

Dominance of S. cerevisiae Commercial Starter Strains during Greco di Tufo and Aglianico Wine Fermentations and Evaluation of Oenological Performances of Some Indigenous/Residential Strains

In order to evaluate dominance/implantation of starter cultures for wine fermentation, both commercial starters and wild strains were monitored during the fermentation of Greco di Tufo (GR) and Aglianico of Taurasi (AGL) musts. Preliminary characterization of commercial strains was carried out by several molecular markers. Five fermentations—four starter-inoculated and one spontaneous—were carried out in duplicates by using grapes from GR and AGL. Trials were monitored, and yeast cultures were isolated within the dominant microflora. Comparison of Interdelta patterns allowed to assess the real occurrence of both starters and indigenous strains. A high genetic diversity within S. cerevisiae strains was detected. In starter-led fermentations (except for few cases), in addition to the starter strains, indigenous S. cerevisiae biotypes were found, as well. Native strains isolated from replicates of the same fermentation showed different genetic profiles. Spontaneous fermentations were conducted, during the first 5 days, by non-Saccharomyces yeasts and, afterwards, by a high number (16 in the AGL and 20 in the GR) of S. cerevisiae biotypes. Indigenous biotypes isolated by GR revealed a high variability in oenological features and, in several cases, showed better performances than those recorded for commercial strains. The study further highlighted the low dominance of some commercial starter cultures. Moreover, autochthonous yeast strains proved to be sometimes more aggressive in terms of fermentation vigor in GR must, likely because better adapted to ecological and technological conditions occurring during winemaking. Finally, the use of such strains for production of autochthonous “pied de cuve” may be a useful strategy for lowering production cost of winemaking.

Genetic and epigenetic dynamics affecting anthocyanin biosynthesis in potato cell culture

Anthocyanins are antioxidant pigments widely used in drugs and food preparations. Flesh-coloured tubers of the cultivated potato Solanum tuberosum are important sources of different anthocyanins. Due to the high degree of decoration achieved by acylation, anthocyanins from potato are very stable and suitable for the food processing industry. The use of cell culture allows to extract anthocyanins on-demand, avoiding seasonality and consequences associated with land-based-tuber production. However, a well-known limit of cell culture is the metabolic instability and loss of anthocyanin production during successive subcultures. To get a general picture of mechanisms responsible for this instability, we explored both genetic and epigenetic regulation that may affect anthocyanin production in cell culture. We selected two clonally related populations of anthocyanin-producing (purple) and non-producing (white) potato cells. Through targeted molecular investigations, we identified and functionally characterized an R3-MYB, here named StMYBATV. This transcription factor can interact with bHLHs belonging to the MBW (R2R3-MYB, bHLH and WD40) anthocyanin activator complex and, potentially, may interfere with its formation. Genome methylation analysis revealed that, for several genomic loci, anthocyanin-producing cells were more methylated than clonally related white cells. In particular, we localized some methylation events in ribosomal protein-coding genes. Overall, our study explores novel molecular aspects associated with loss of anthocyanins in cell culture systems.

Notulae to the Italian alien vascular flora: 9

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions. Furthermore, three new combinations are proposed. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

WRKY genes family study reveals tissue-specific and stress-responsive TFs in wild potato species

Wild potatoes, as dynamic resource adapted to various environmental conditions, represent a powerful and informative reservoir of genes useful for breeding efforts. WRKY transcription factors (TFs) are encoded by one of the largest families in plants and are involved in several biological processes such as growth and development, signal transduction, and plant defence against stress. In this study, 79 and 84 genes encoding putative WRKY TFs have been identified in two wild potato relatives, Solanum commersonii and S. chacoense. Phylogenetic analysis of WRKY proteins divided ScWRKYs and SchWRKYs into three Groups and seven subGroups. Structural and phylogenetic comparative analyses suggested an interspecific variability of WRKYs. Analysis of gene expression profiles in different tissues and under various stresses allowed to select ScWRKY045 as a good candidate in wounding-response, ScWRKY055 as a bacterial infection triggered WRKY and ScWRKY023 as a multiple stress-responsive WRKY gene. Those WRKYs were further studied through interactome analysis allowing the identification of potential co-expression relationships between ScWRKYs/SchWRKYs and genes of various pathways. Overall, this study enabled the discrimination of WRKY genes that could be considered as potential candidates in both breeding programs and functional studies.

Genome-Wide HMG Family Investigation and Its Role in Glycoalkaloid Accumulation in Wild Tuber-Bearing Solanum commersonii

Steroidal glycoalkaloids (SGAs) are a class of nitrogen-containing glycosides occurring in several plant families and biosynthesized through a specific pathway. HMG-CoA reductase is the first enzyme of this pathway, and its transcription can be regulated by biotic and abiotic stressors and even in a tissue-specific manner. This study aimed to characterize the HMG genes family in a tuber-bearing potato species, Solanum commersonii, using transcriptional and functional approaches. Our results provided evidence that four ScHMGs with different tissue-specificities represent the HMG gene family in S. commersonii and that they originated from ScHMG1 through segmental duplications. Phylogenetic analysis suggests that ScHMG1 is the direct ortholog of AtHMG1, which is associated with SGAs accumulation in plants. Its overexpression in S. commersonii revealed that this gene plays a key role in the accumulation of glycoalkaloids regulating the production of dehydrocommersonine.

Deep-sequencing of Solanum commersonii small RNA libraries reveals riboregulators involved in cold stress response

Among wild species used in potato breeding, Solanum commersonii displays the highest tolerance to low temperatures under both acclimated (ACC) and non-acclimated (NACC) conditions. It is also the first wild potato relative with a known whole genome sequence. Recent studies have shown that abiotic stresses induce changes in the expression of many small non-coding RNA (sncRNA). We determined the small non-coding RNA (sncRNAome) of two clones of S. commersonii contrasting in their cold response phenotypes via smRNAseq. Differential analysis provided evidence that expression of several miRNAs changed in response to cold stress conditions. Conserved miR408a and miR408b changed their expression under NACC conditions, whereas miR156 and miR169 were differentially expressed only under ACC conditions. We also report changes in tasiRNA and secondary siRNA expression under both stress conditions. Our results reveal possible roles of sncRNA in the regulatory networks associated with tolerance to low temperatures and provide useful information for a more strategic use of genomic resources in potato breeding.

Transcriptional, metabolic and DNA methylation changes underpinning the response of Arundo donax ecotypes to NaCl excess

Arundo donax ecotypes react differently to salinity, partly due to differences in constitutive defences and methylome plasticity. Arundo donax L. is a C3 fast-growing grass that yields high biomass under stress. To elucidate its ability to produce biomass under high salinity, we investigated short/long-term NaCl responses of three ecotypes through transcriptional, metabolic and DNA methylation profiling of leaves and roots. Prolonged salt treatment discriminated the sensitive ecotype 'Cercola' from the tolerant 'Domitiana' and 'Canneto' in terms of biomass. Transcriptional and metabolic responses to NaCl differed between the ecotypes. In roots, constitutive expression of ion transporter and stress-related transcription factors' genes was higher in 'Canneto' and 'Domitiana' than 'Cercola' and 21-day NaCl drove strong up-regulation in all ecotypes. In leaves, unstressed 'Domitiana' confirmed higher expression of the above genes, whose transcription was repressed in 'Domitiana' but induced in 'Cercola' following NaCl treatment. In all ecotypes, salinity increased proline, ABA and leaf antioxidants, paralleled by up-regulation of antioxidant genes in 'Canneto' and 'Cercola' but not in 'Domitiana', which tolerated a higher level of oxidative damage. Changes in DNA methylation patterns highlighted a marked capacity of the tolerant 'Domitiana' ecotype to adjust DNA methylation to salt stress. The reduced salt sensitivity of 'Domitiana' and, to a lesser extent, 'Canneto' appears to rely on a complex set of constitutively activated defences, possibly due to the environmental conditions of the site of origin, and on higher plasticity of the methylome. Our findings provide insights into the mechanisms of adaptability of A. donax ecotypes to salinity, offering new perspectives for the improvement of this species for cultivation in limiting environments.

Inferring RPW8-NLRs's evolution patterns in seed plants: case study in Vitis vinifera

Genomic and transcriptomic studies in plants and, more in deep, in grapevine reveal that the disease-resistance RNL gene family is highly variable. RNLs (RPW8-NLRs) are a phylogenetically distinct class of nucleotide oligomerization domain (NOD)-like receptors (NLRs) identified in plants. Two RNLs, namely, the NRG1 (N Requirement Gene 1) and the ADR1 (Activated Disease Resistance 1), have been characterized; however, little is known about the RNL evolutionary history in higher plants. To trace the diversification of RNL gene subfamily, we scanned the NLR proteins of 73 plant genomes belonging to 29 taxa, revealing a noticeable diversification across species and within the same genus or botanic family together with a conspicuous expansion in important crop species. To explore the RNL variability in Vitis vinifera and gain information with respect to their structure, evolutionary diversification of five grape genomes ('Aglianico', 'Falanghina', 'Sultanina', 'Tannat', and 'Nebbiolo') has been compared to the reference genome ('Pinot Noir'). The number of RNLs ranged from 6 ('Sultanina') to 14 ('Nebbiolo'), in contrast to the 10 'Pinot Noir' RNLs. The phylogenetic study on grapevine RNLs revealed that all collapsed into NRG1-clade, rather than four. To investigate more in depth the means of intraspecific variability of grape RNL copies, a transcriptomic profiling in response to powdery mildew (PM) infection was carried out through qRT-PCRs and public databases interrogation. The RNL expression variability identified in transcriptome data sets supports the hypothesis of a functional expansion/contraction in grapevine varieties. Although no direct correlations between grapevine PM-resistance and RNL expression was identified, our work can provide good candidates for functional studies able to elucidate the putative "helper" role of RNLs in grape immune signalling.

The grapevine (Vitis vinifera) LysM receptor kinases VvLYK1-1 and VvLYK1-2 mediate chitooligosaccharide-triggered immunity

Chitin, a major component of fungal cell walls, is a well-known pathogen-associated molecular pattern (PAMP) that triggers defense responses in several mammal and plant species. Here, we show that two chitooligosaccharides, chitin and chitosan, act as PAMPs in grapevine (Vitis vinifera) as they elicit immune signalling events, defense gene expression and resistance against fungal diseases. To identify their cognate receptors, the grapevine family of LysM receptor kinases (LysM-RKs) was annotated and their gene expression profiles were characterized. Phylogenetic analysis clearly distinguished three V. vinifera LysM-RKs (VvLYKs) located in the same clade as the Arabidopsis CHITIN ELICITOR RECEPTOR KINASE1 (AtCERK1), which mediates chitin-induced immune responses. The Arabidopsis mutant Atcerk1, impaired in chitin perception, was transformed with these three putative orthologous genes encoding VvLYK1-1, -2, or -3 to determine if they would complement the loss of AtCERK1 function. Our results provide evidence that VvLYK1-1 and VvLYK1-2, but not VvLYK1-3, functionally complement the Atcerk1 mutant by restoring chitooligosaccharide-induced MAPK activation and immune gene expression. Moreover, expression of VvLYK1-1 in Atcerk1 restored penetration resistance to the non-adapted grapevine powdery mildew (Erysiphe necator). On the whole, our results indicate that the grapevine VvLYK1-1 and VvLYK1-2 participate in chitin- and chitosan-triggered immunity and that VvLYK1-1 plays an important role in basal resistance against E. necator.

Transcriptome reprogramming, epigenetic modifications and alternative splicing orchestrate the tomato root response to the beneficial fungus Trichoderma harzianum

Beneficial interactions of rhizosphere microorganisms are widely exploited for plant biofertilization and mitigation of biotic and abiotic constraints. To provide new insights into the onset of the roots-beneficial microorganisms interplay, we characterised the transcriptomes expressed in tomato roots at 24, 48 and 72 h post inoculation with the beneficial fungus Trichoderma harzianum T22 and analysed the epigenetic and post-trascriptional regulation mechanisms. We detected 1243 tomato transcripts that were differentially expressed between Trichoderma-interacting and control roots and 83 T. harzianum transcripts that were differentially expressed between the three experimental time points. Interaction with Trichoderma triggered a transcriptional response mainly ascribable to signal recognition and transduction, stress response, transcriptional regulation and transport. In tomato roots, salicylic acid, and not jasmonate, appears to have a prominent role in orchestrating the interplay with this beneficial strain. Differential regulation of many nutrient transporter genes indicated a strong effect on plant nutrition processes, which, together with the possible modifications in root architecture triggered by ethylene/indole-3-acetic acid signalling at 72 h post inoculation may concur to the well-described growth-promotion ability of this strain. Alongside, T. harzianum-induced defence priming and stress tolerance may be mediated by the induction of reactive oxygen species, detoxification and defence genes. A deeper insight into gene expression and regulation control provided first evidences for the involvement of cytosine methylation and alternative splicing mechanisms in the plant-Trichoderma interaction. A model is proposed that integrates the plant transcriptomic responses in the roots, where interaction between the plant and beneficial rhizosphere microorganisms occurs.

Dicer-like and RNA-dependent RNA polymerase gene family identification and annotation in the cultivated Solanum tuberosum and its wild relative S. commersonii

We provide advances in DCL and RDR gene diversity in Solanaceae. We also shed light on DCL and RDR gene expression in response to cold stress. DICER-like (DCL) and RNA-dependent RNA polymerase (RDR) genes form the core components to trigger small non-coding RNA (ncRNA) production. In spite of this, little is known about the two gene families in non-model plant species. As their genome sequences are now available, the cultivated potato (Solanum tuberosum) and its cold-tolerant wild relative Solanum commersonii offer a valuable opportunity to advance our understanding of the above genes. To determine the extent of diversification and evolution of DCLs and RDRs in these species, we performed a comparative analysis. Seven DCLs were identified in the two species, whereas seven and six RDR genes were found in S. tuberosum and S. commersonii, respectively. Based on phylogenetic analysis with DCLs and RDRs from several species, we provide evidence for an increase in their number in both potato species. We also disclosed that tandem duplications played a major role in the evolution of these gene families in Solanaceae. DCL and RDR expression was investigated in different tissues and under cold and virus stresses, with divergent profiles of the tandem duplicated genes being found in different tissues. DCL paralogs showed a contrasting expression in S. tuberosum and S. commersonii following cold stress and virus infection. By contrast, no change in RDR transcript activity was detected following both stresses. Overall, this study provides the first comparative genomic analysis of the core components of the RNAi machinery in Solanaceae and offers a scaffold for future functional analysis of these gene families.

Metabolic and RNA profiling elucidates proanthocyanidins accumulation in Aglianico grape

Aglianico grapes are known for their high content of proanthocyanidins (PAs), which are responsible for the astringency of wines derived from this cultivar. However, the accumulation of PAs and their genetic control during berry development remain largely unexplored. This work aimed to monitor astringency-causing PAs in Aglianico berries and correlate them with the expression of 14 key genes. Berries were collected during ripening and dissected in skins and seeds. PAs were fractionated and the content of total phenolics, flavans, anthocyanins, tannins reactive towards salivary proteins and tannin structural composition were evaluated. The results provided evidence that PAs were more abundant in seeds than in skins as expected, with differences in the structural composition between tissues, which did not varied during ripening. Expression analysis showed that Aglianico is able to accumulate polyphenols due to its ability to modulate key genes in a tissue-specific manner.

Combined Use of Molecular Markers and High-Resolution Melting (HRM) to Assess Chromosome Dosage in Potato Hybrids

In plants, the most widely used cytological techniques to assess parental genome contributions are based on in situ hybridization (FISH and GISH), but they are time-consuming and need specific expertise and equipment. Recent advances in genomics and molecular biology have made PCR-based markers a straightforward, affordable technique for chromosome typing. Here, we describe the development of a molecular assay that uses single-copy conserved ortholog set II (COSII)-based single nucleotide polymorphisms (SNPs) and the high-resolution melting (HRM) technique to assess the chromosome dosage of interspecific hybrids between a Solanum phureja-S. tuberosum diploid (2n = 2x = 24) hybrid and its wild relative S. commersonii. Screening and analysis of 45 COSII marker sequences allowed S. commersonii-specific SNPs to be identified for all 12 chromosomes. Combining the HRM technique with the establishment of synthetic DNA hybrids, SNP markers were successfully used to predict the expected parental chromosome ratio of 5 interspecific triploid hybrids. These results demonstrate the ability of this strategy to distinguish diverged genomes from each other, and to estimate chromosome dosage. The method could potentially be applied to any species as a tool to assess paternal to maternal ratios in the framework of a breeding program or following transformation techniques.

Lymphoscintigraphy with intraoperative gamma probe sentinel node detection: clinical impact in patients with head and neck melanomas

AIM

The aims of this paper were to evaluate the clinical relevance of lymphoscintigraphy with intraoperative gamma-probe detection in identifying sentinel nodes (SNs) and to study the prognostic value of SN biopsy in head and neck melanoma patients.

METHODS

Sixty-one patients had lymphoscintigraphy with intradermal injections of 99mTc-Nanocoll (40 MBq), 24 h before surgery. Tumor-positive SNs patients underwent total lymph node dissection. Postoperative histological examination was performed. Patients were followed up for 1 to 5 years (median 3 years). The tumor relapses and the overall survival were evaluated by means of statistical methods.

RESULTS

Lymphoscintigraphy showed lymphatic distribution to more than one basin in 45 patients (74%), in 15 patients one basin was visualized and no basin in 1 patient. In 41 patients the SN was negative for metastases, while in 20 was positive. In a high percentage of patients (30%), metastatic involvement occurred in more than one lymph node basin. During follow-up in the negative SN group, 40 patients remained disease free and 1 relapsed. In the positive SN group, 10 patients remained disease free and 10 relapsed. Recurrence time ranged from 6 to 11 months. The overall survival of the SNs negative group was significantly higher than the positive SN group.

CONCLUSIONS

This approach was able to distinguish: a) patients with tumor-negative SNs with a favorable clinical course (98% did not relapse, P<0.001); b) patients with tumor-positive SNs with a high rate of tumor relapse (50%, P<0.001). Therefore SN biopsy may give information about prognosis in head and neck melanoma patients.

Comparative evaluation of two methods to assay thyroglobulin serum concentrations in patients with differentiated thyroid carcinomas

AIM

This study was aimed at the comparative assessment of the analytical and clinical performances of 2 tests for thyroglobulin (Tg) assays: the Dynotest Tg-Plus immunoradiometric assay (IRMA), a new method that might be of interest for its claimed superior sensitivity compared to other methods, and the HTGK-2 IRMA, one of the test currently used in clinical routine.

METHODS

The study was performed in serum samples from 157 patients with differentiated thyroid carcinoma (DTC). The clinical sensitivity of the test was evaluated in patients with and without thyroid stimulating hormone (TSH) suppression.

RESULTS

The lowest detectable Tg concentration values and the within-assay coefficient of variation (CV) were 0.4 and 0.8 microg/L and 5% and 3% for the Dynotest Tg-Plus assay and the HTGK-2 assay, respectively; the between-assay CV was 6% for both assays. The clinical results of the Dynotest Tg-Plus and those of the HTGK-2 kit were similar in both DTC patient populations, either under or off the TSH suppressive treatment. In spite of the manufacturer's statement that the calibrators of both assays had been standardized against the same common reference (standard CRM 457 of the Community Bureau of References), the Dynotest Tg-Plus test underrated by a factor of 0.5 the Tg values measured by means of HTGK-2 IRMA.

CONCLUSION

The sensitivity of the Dynotest Tg-Plus IRMA appears to be similar to that of the HTGK-2 assay.

Position of nuclear medicine techniques in the diagnostic work-up of neuroendocrine tumors

In recent years nuclear medicine has contributed to the impressive development of the knowledge of neuroendocrine tumors in terms of biology (receptor scintigraphy), pharmacology (development of new tracers), and therapy (radiometabolic therapy). At present, it is impossible to plan the management of a patient affected by a neuroendocrine tumor without performing nuclear medicine examinations. The contribution of nuclear medicine had affected and improved the management of these patients by offering various important options that are part of the modern diagnosis and treatment protocols. The clinical experience and the literature confirm that, among the wide variety of tracers and nuclear medicine modalities available today, metaiodobenzylguanidine (MIBG) and DTPA-D-Phe-octreotide (pentetreotide) are the radiopharmaceuticals of current clinical use. Several new somatostatin analogues are under investigation. Positron emission tomography (PET) supplies a range of labelled compounds to be used for the visualization of tumor biochemistry. In addition to the first routinely used PET tracer in oncology, 18F-labelled deoxyglucose (FDG), a number of radiopharmaceuticals based on different precursors such as fluorodopamine and 5-hydroxytryptophan (5-HTP) are going to gain a clinical role. Of course, the diagnosis of neuroendocrine tumors has to be based on integrated information derived from different examinations including nuclear medicine studies. The clinical presentation of neuroendocrine tumors is highly variable: sometimes they manifest typical or atypical symptoms but they may also be detected by chance during an X-ray or ultrasound examination carried out for other reasons. At disease presentation nuclear medicine modalities are sometimes able to direct physicians towards the clinical diagnosis thanks to the specificity of their imaging mechanisms. They also play a role in disease staging and restaging, patient follow-up and treatment monitoring. In addition, the biological characterisation of neuroendocrine tissues (receptor status, glucose metabolism, differentiation, etc.) allows the interpretation of radiopharmaceutical uptake as a prognostic parameter and sometimes as a predictor of the response to treatment.

Gallium scan in adolescents and children with Hodgkin's disease (HD). Treatment response assessment and prognostic value

AIM

The aim of the present paper is to describe the accuracy of gallium ((67)Ga) scintigraphy in adolescents and children with Hodgkin's disease (HD). We have studied the diagnostic value of this nuclear imaging technique at disease presentation (staging) and its prognostic value based on changes in (67)Ga uptake observed after treatment (response assessment).

METHODS

From April 1985 to July 1999 74 consecutive untreated patients with a median age of 13 y underwent (67)Ga scans 48-72 h after injection of 37-111 MBq of (67)Ga-citrate. Planar whole-body scintigraphy was performed, supplemented with single photon emission tomography (SPET) of the mediastinum from 1996 onwards. Three patients did not undergo further scintigraphic examination because they were treated with radical surgery. After the 1st examination 71 of the 74 patients were monitored by 1-3 (67)Ga scans during the course of their disease. All of them had at least one (67)Ga scintigraphy at the end of the induction phase of chemotherapy, before any other therapeutic regimens were planned.

RESULTS

At disease presentation (67)Ga scintigraphy was positive in all patients, detecting 285 of 335 (85.0%) lymph nodal sites of disease. The best sensitivity was observed in the mediastinum (100%; 63/63) and the laterocervical supraclavicular region (85.6%; 125/146); it was lower for axillary (72.7%; 16/22) and retroperitoneal (68.7%; 11/16) lymph node masses. In detecting visceral involvement the sensitivity of (67)Ga scintigraphy was 66.6% (8/12) for lung and 80% (4/5) for bone involvement. Among 71 patients in follow-up, 2 showed rapid progression of disease during induction therapy while 69 patients were monitored for a long period. The response to therapy has been classified according to the changes observed on nuclear medicine or radiological images as complete response (CR) or partial response (PR). On the basis of (67)Ga scans 55 patients (72.4%) were considered as having a CR, while with radiological modalities (chest X-ray, CT, MRI) CR was observed in only 29 patients (40.8%). PR or progression was found with (67)Ga scintigraphy in 16 patients (22.5%) and with radiological modalities in 42 patients (59.1%). (67)Ga scan was concordant with clinical outcome in 97% (28/29). The diagnostic effectiveness of this imaging technique has been analysed by comparing the scintigraphic or radiological changes at the 1st scintigraphic/radiological follow-up examination after induction therapy with the clinical outcome. In this population the relapse rate was 50% (8/16) in the group that did not achieve a CR according to post-treatment (67)Ga scintigraphy, while it was only 10.9% (6/55) in the group that achieved a CR on the basis of scintigraphy findings. The overall survival (OS) and disease-free survival (DFS) were calculated by means of Kaplan-Meier cumulative survival plotting. When the 2 groups of patients with complete (CR) or incomplete normalisation (PR or progression) of (67)Ga scintigraphy were compared, both OS and DFS were found to be statistically different (p=0.0001 and p=0.0004, respectively). By contrast, no statistical difference was found when the radiological findings were considered as the criterion for assessment of tumour response. On the basis of X-ray results the relapse rate was 13.7% in patients with negative post-therapy findings and 23.8% in patients with positive radiological imaging.

CONCLUSION

Our data demonstrate the high value of (67)Ga scintigraphy in HD staging in paediatric patients. In addition, evaluation of the (67)Ga uptake is very useful as a prognostic parameter; changes in (67)Ga uptake after therapy indicate a favourable prognosis, whereas children still positive on post-treatment (67)Ga scintigrams should be given more aggressive treatment.