Solanum pennellii (LA5240) backcross inbred lines (BILs) for high resolution mapping in tomato

Wild species are an invaluable source of new traits for crop improvement. Over the years, the tomato community bred cultivated lines that carry introgressions from different species of the tomato tribe to facilitate trait discovery and mapping. The next phase in such projects is to find the genes that drive the identified phenotypes. This can be achieved by genotyping a few thousand individuals resulting in fine mapping that can potentially identify the causative gene. To couple trait discovery and fine mapping, we are presenting large, recombination-rich, Backcross Inbred Line (BIL) populations involving an unexplored accession of the wild, green-fruited species Solanum pennellii (LA5240; the 'Lost' Accession) with two modern tomato inbreds: LEA, determinate, and TOP, indeterminate. The LEA and TOP BILs are in BC2F6-8 generation and include 1400 and 500 lines, respectively. The BILs were genotyped with 5000 SPET markers, showing that in the euchromatic regions there was one recombinant every 17-18 Kb while in the heterochromatin a recombinant every 600-700 Kb (TOP and LEA respectively). To gain perspective on the topography of recombination we compared five independent members of the Self-pruning gene family with their respective neighboring genes; based on PCR markers, in all cases we found recombinants. Further mapping analysis of two known morphological mutations that segregated in the BILs (self-pruning and hairless) showed that the maximal delimited intervals were 73 Kb and 210 Kb, respectively, and included the known causative genes. The 'Lost'_BILs provide a solid framework to study traits derived from a drought-tolerant wild tomato.

Analysis of >3400 worldwide eggplant accessions reveals two independent domestication events and multiple migration-diversification routes

Eggplant (Solanum melongena) is an important Solanaceous crop, widely cultivated and consumed in Asia, the Mediterranean basin, and Southeast Europe. Its domestication centers and migration and diversification routes are still a matter of debate. We report the largest georeferenced and genotyped collection to this date for eggplant and its wild relatives, consisting of 3499 accessions from seven worldwide genebanks, originating from 105 countries in five continents. The combination of genotypic and passport data points to the existence of at least two main centers of domestication, in Southeast Asia and the Indian subcontinent, with limited genetic exchange between them. The wild and weedy eggplant ancestor S. insanum shows admixture with domesticated S. melongena, similar to what was described for other fruit-bearing Solanaceous crops such as tomato and pepper and their wild ancestors. After domestication, migration and admixture of eggplant populations from different regions have been less conspicuous with respect to tomato and pepper, thus better preserving 'local' phenotypic characteristics. The data allowed the identification of misclassified and putatively duplicated accessions, facilitating genebank management. All the genetic, phenotypic, and passport data have been deposited in the Open Access G2P-SOL database, and constitute an invaluable resource for understanding the domestication, migration and diversification of this cosmopolitan vegetable.

Generation and physiological characterization of genome-edited Nicotiana benthamiana plants containing zeaxanthin as the only leaf xanthophyll

MAIN CONCLUSION

Simultaneous genome editing of the two homeologous LCYe and ZEP genes of Nicotiana benthamiana results in plants in which all xanthophylls are replaced by zeaxanthin. Plant carotenoids act both as photoreceptors and photoprotectants in photosynthesis and as precursors of apocarotenoids, which include signaling molecules such as abscisic acid (ABA). As dietary components, the xanthophylls lutein and zeaxanthin have photoprotective functions in the human macula. We developed transient and stable combinatorial genome editing methods, followed by direct LC-MS screening for zeaxanthin accumulation, for the simultaneous genome editing of the two homeologous Lycopene Epsilon Cyclase (LCYe) and the two Zeaxanthin Epoxidase (ZEP) genes present in the allopolyploid Nicotiana benthamiana genome. Editing of the four genes resulted in plants in which all leaf xanthophylls were substituted by zeaxanthin, but with different ABA levels and growth habits, depending on the severity of the ZEP1 mutation. In high-zeaxanthin lines, the abundance of the major photosystem II antenna LHCII was reduced with respect to wild-type plants and the LHCII trimeric state became unstable upon thylakoid solubilization. Consistent with the depletion in LHCII, edited plants underwent a compensatory increase in PSII/PSI ratios and a loss of the large-size PSII supercomplexes, while the level of PSI-LHCI supercomplex was unaffected. Reduced activity of the photoprotective mechanism NPQ was shown in high-zeaxanthin plants, while PSII photoinhibition was similar for all genotypes upon exposure to excess light, consistent with the antioxidant and photoprotective role of zeaxanthin in vivo.

A multi-omic Nicotiana benthamiana resource for fundamental research and biotechnology

Nicotiana benthamiana is an invaluable model plant and biotechnology platform with a ~3 Gb allotetraploid genome. To further improve its usefulness and versatility, we have produced high-quality chromosome-level genome assemblies, coupled with transcriptome, epigenome, microRNA and transposable element datasets, for the ubiquitously used LAB strain and a related wild accession, QLD. In addition, single nucleotide polymorphism maps have been produced for a further two laboratory strains and four wild accessions. Despite the loss of five chromosomes from the ancestral tetraploid, expansion of intergenic regions, widespread segmental allopolyploidy, advanced diploidization and evidence of recent bursts of Copia pseudovirus (Copia) mobility not seen in other Nicotiana genomes, the two subgenomes of N. benthamiana show large regions of synteny across the Solanaceae. LAB and QLD have many genetic, metabolic and phenotypic differences, including disparate RNA interference responses, but are highly interfertile and amenable to genome editing and both transient and stable transformation. The LAB/QLD combination has the potential to be as useful as the Columbia-0/Landsberg errecta partnership, utilized from the early pioneering days of Arabidopsis genomics to today.

In Vivo Functional Properties of Dairy Bacteria

This literature review aimed to collect investigations on the in vivo evidence for bacteria associated with fermented dairy foods to behave as probiotics with beneficial effects in the prevention and treatment of various diseases. All main bacterial groups commonly present in high numbers in fermented milks or cheeses were taken into account, namely starter lactic acid bacteria (SLAB) Lactobacillus delbrueckii subsp. bulgaricus and lactis, L. helveticus, Lactococcus lactis, Streptococcus thermophilus, non-starter LAB (NSLAB) Lacticaseibacillus spp., Lactiplantibacillus plantarum, dairy propionibacteria, and other less frequently encountered species. Only studies regarding strains of proven dairy origin were considered. Studies in animal models and clinical studies showed that dairy bacteria ameliorate symptoms of inflammatory bowel disease (IBD), mucositis, metabolic syndrome, aging and oxidative stress, cancer, bone diseases, atopic dermatitis, allergies, infections and damage caused by pollutants, mild stress, and depression. Immunomodulation and changes in the intestinal microbiota were the mechanisms most often involved in the observed effects. The results of the studies considered indicated that milk and dairy products are a rich source of beneficial bacteria that should be further exploited to the advantage of human and animal health.

Cross-sectional study of hepatitis E virus (HEV) circulation in Italian pig farms

Foodborne transmission is considered the main way of spreading zoonotic hepatitis E virus (HEV) infection in Europe. In recent years, the human cases of hepatitis E in subjects without history of travel in endemic areas have raised, suggesting that domestic HEV transmission is increasing. Pork products with or without liver, are often indicated as the source of many human foodborne HEV cases as well as small outbreaks. Pigs are recognized as the main reservoir of the zoonotic HEV-3 genotype, the most frequently detected in human cases in the EU. In the absence of a harmonized surveillance of HEV circulation, data on prevalence are heterogeneous but confirm a widespread circulation of HEV-3 in pig herds across EU. HEV-3 can pass through the food chain from farm to fork when infected animals are slaughtered. In Italy, several studies reported the circulation of HEV-3 in pig farms, but results are heterogeneous due to different methodologies applied. In the present study, we performed a survey over 51 pig herds belonging to three main types of farms: breeding, fattening and farrow-to-finish. HEV-RNA was analyzed by broad range Real-time RT-PCR on 20 samples for each farm, obtained by pooling together feces from 10 individuals. Overall, HEV RNA was confirmed on 150 fecal pooled samples out of 1,032 (14.5%). At least one positive pooled sample was detected from 18 farms out of 51 tested (35.3%). By lowering the number of infected pigs at primary production, the risk of HEV-3 entering into the food chain can be reduced. Hence, information on HEV circulation in herds is highly relevant for choosing preventive measures and deserves development of a monitoring program and further investigations.

Heterologous expression of Bixa orellana cleavage dioxygenase 4-3 drives crocin but not bixin biosynthesis

Annatto (Bixa orellana) is a perennial shrub native to the Americas, and bixin, derived from its seeds, is a methoxylated apocarotenoid used as a food and cosmetic colorant. Two previous reports claimed to have isolated the carotenoid cleavage dioxygenase (CCD) responsible for the production of the putative precursor of bixin, the C24 apocarotenal bixin dialdehyde. We re-assessed the activity of six Bixa CCDs and found that none of them produced substantial amounts of bixin dialdehyde in Escherichia coli. Unexpectedly, BoCCD4-3 cleaved different carotenoids (lycopene, β-carotene, and zeaxanthin) to yield the C20 apocarotenal crocetin dialdehyde, the known precursor of crocins, which are glycosylated apocarotenoids accumulated in saffron stigmas. BoCCD4-3 lacks a recognizable transit peptide but localized to plastids, the main site of carotenoid accumulation in plant cells. Expression of BoCCD4-3 in Nicotiana benthamiana leaves (transient expression), tobacco (Nicotiana tabacum) leaves (chloroplast transformation, under the control of a synthetic riboswitch), and in conjunction with a saffron crocetin glycosyl transferase, in tomato (Solanum lycopersicum) fruits (nuclear transformation) led to high levels of crocin accumulation, reaching the highest levels (>100 µg/g dry weight) in tomato fruits, which also showed a crocin profile similar to that found in saffron, with highly glycosylated crocins as major compounds. Thus, while the bixin biosynthesis pathway remains unresolved, BoCCD4-3 can be used for the metabolic engineering of crocins in a wide range of different plant tissues.

The role of staff and contaminated environmental surfaces in spreading of norovirus infection in a long-term health care facility in Italy

Some residents and people from the staff of a geriatric health care facility in Teramo province, developed acute gastroenteritis from March 8th to March 21st 2017. A prompt epidemiological investigation was conducted to identify the etiological agent, the trace back the potential ways of transmission and control the infection. Information on the outbreak was collected through an epidemiological questionnaire. Faecal samples from all human cases (n = 50) and swabs from environmental surfaces were collected and analysed by RT-PCR for the presence of Norovirus (NoV). Among faecal samples, 34 out of 50 were positive for NoV with no other pathogen detected. In particular, 2 (2/34) were positive to NoV genogroup I (GI), 31 (31/34) to NoV genogroup II (GII), and one sample (1/34) was positive to both NoV GI and GII. Moreover, faecal samples of people from the canteen (n = 8) were also tested resulting negative to NoV detection. Norovirus was also detected in 28 of the 122 swabs from environmental surfaces collected. Among the positive samples, 12 NoV strains were subtyped as NoV GII.4 Sydney_2012 variant. Person-to-person close contact and contaminated environmental surfaces were the probable transmission route among the people of the health care facility. The members of the staff were considered to play an important role in transmission of NoV. A proper disinfection procedure applied during the outbreak could have been critically important to limit the dissemination of the viral infection.

Molecular detection of HEV in domestic pigs in Italy from Abruzzo and Molise regions

Background

Hepatitis E virus (HEV) is a zoonotic pathogen transmitted through the faecal-oral route and it is responsible of disease in humans with more than 21.000 cases reported in the European Union (EU) over the last decade. It is a non-enveloped single stranded RNA virus that includes 8 genotypes; among these, genotypes 3 and 4 (HEV-3 and HEV-4) are the most prevalent in developed countries and infect both humans and some animal species such as domestic pigs. In this study, we investigated the prevalence of HEV in domestic pigs bred in Italy, in Abruzzo and Molise regions.

Methods

During the period October 2020-March 2021, 327 liver samples from individual pigs were analysed. In particular, 211 were collected in 1 slaughterhouse and originated from animals bred in Abruzzo in 8 different farms and 116 were collected in 7 slaughterhouses and originated from animals bred in Molise in 47 farms. The real time retro-transcriptase (RT)-polymerase chain reaction (PCR) technique was used to detect HEV by targeting the open reading frame (ORF) 3 region of the viral ribonucleic acid (RNA).

Results

None of the samples deriving from pigs bred in Abruzzo tested positive for the detection of HEV RNA. Instead, 4 samples from pigs bred in 2 different farms in Molise tested positive, showing a prevalence of 3.45%.

Conclusions

Pigs are considered important reservoirs for HEV virus. For this reason, it is opportune to investigate the role of these animals for better understanding their involvement in the human infection through the consumption of contaminated raw or undercooked pork-meat products. These findings need to be further investigated with in depth genomic characterization of positive RNA samples to highlight the role of the specific strains circulating in this region and to draw conclusions about connections between animals, potential contaminated food and human disease.

Key messages

The study paved the way for defining the role of pigs in the transmission of HEV virus to humans through the consumption of pork meat products. This study reports the prevalence of HEV in domestic pigs of Abruzzo and Molise regions, two Italian regions.

Bacteriophage Therapy to Reduce Colonization of Campylobacter jejuni in Broiler Chickens before Slaughter

Campylobacteriosis is the most commonly reported gastrointestinal disease in humans. Campybacter jejuni is the main cause of the infection, and bacterial colonization in broiler chickens is widespread and difficult to prevent, leading to high risk of occurrence in broiler meat. Phage therapy represents an alternative strategy to control Campylobacter in poultry. The aim of this work was to assess the efficacy of two field-isolated bacteriophages against experimental infections with an anti-microbial resistant (AMR) Campylobacter jejuni strain. A two-step phage application was tested according to a specific combination between chickens’ rearing time and specific multiplicities of infections (MOIs), in order to reduce the Campylobacter load in the animals at slaughtering and to limit the development of phage-resistant mutants. In particular, 75 broilers were divided into three groups (A, B and C), and phages were administered to animals of groups B and C at day 38 (Φ 16-izsam) and 39 (Φ 7-izsam) at MOI 0.1 (group B) and 1 (group C). All broilers were euthanized at day 40, and Campylobacter jejuni was enumerated in cecal contents. Reductions in Campylobacter counts were statistically significant in both group B (1 log₁₀ colony forming units (cfu)/gram (gr)) and group C (2 log₁₀ cfu/gr), compared to the control group. Our findings provide evidence about the ability of phage therapy to reduce the Campylobacter load in poultry before slaughtering, also associated with anti-microbial resistance pattern.

Characterization and In Vitro Efficacy against Listeria monocytogenes of a Newly Isolated Bacteriophage, ɸIZSAM-1

Listeria monocytogenes is a bacterial pathogen responsible of listeriosis, a disease that in humans is often related to the contamination of ready-to-eat foods. Phages are candidate biodecontaminants of pathogenic bacteria thanks to their ability to lyse prokaryotes while being safe for eukaryotic cells. In this study, ɸIZSAM-1 was isolated from the drain-waters of an Italian blue cheese plant and showed lytic activity against antimicrobial resistant Listeria monocytogenes strains. This phage was subjected to purification and in vitro efficacy tests. The results showed that at multiplicities of infection (MOIs) ≤ 1, phages were able to keep Listeria monocytogenes at low optical density values up to 8 h, with bacterial counts ranging from 1.02 to 3.96 log10 units lower than the control. Besides, ɸIZSAM-1 was further characterized, showing 25 principal proteins (sodium dodecyl sulfate polyacrylamide gel electrophoresis profile) and a genome of approximately 50 kilo base pairs. Moreover, this study describes a new approach to phage isolation for applications in Listeriamonocytogenes biocontrol in food production. In particular, the authors believe that the selection of phages from the same environments where pathogens live could represent a new approach to successfully integrating the control measures in an innovative, cost effective, safe and environmentally friendly way.

Whole Genome Sequencing Characterization of HEV3-e and HEV3-f Subtypes among the Wild Boar Population in the Abruzzo Region, Italy: First Report

Hepatitis E virus (HEV) is an emergent zoonotic pathogen, causing worldwide acute and chronic hepatitis in humans. HEV comprises eight genotypes and several subtypes. HEV genotypes 3 and 4 (HEV3 and HEV4) are zoonotic. In Italy, the most part of HEV infections (80%) is due to autochthonous HEV3 circulation of the virus, and the key role played by wild animals is generally accepted. Abruzzo is an Italian region officially considered an HEV "hot spot", with subtype HEV3-c being up to now the only one reported among wild boars. During the year 2018-2019, a group of wild boars in Abruzzo were screened for HEV; positive RNA liver samples were subjected to HEV characterization by using the whole genome sequencing (WGS) approach methodology. This represents the first report about the detection of HEV-3 subtypes e and f in the wild boar population in this area. Since in Italy human infections from HEV 3-e and f have been associated with pork meat consumption, our findings deserve more in-depth analysis with the aim of evaluating any potential correlation between wild animals, the pork chain production and HEV human infections.

Root internalization of Salmonella Typhimurium in basil plants

Background

Foodborne pathogens present in soil or irrigation water have the potential to internalize via root into edible parts of the plants and survive, representing a serious hazard for consumer's health (1). The present work assesses the ability of Salmonella Typhimurium (ST) to enter basil plants (Ocimum basilicum L., cultivar “Napoletano”) from roots. This situation may represent a risk in food safety since that vegetable is largely used raw/undercooked, in the Mediterranean diet.

Methods

Sixteen basil plants were cultivated in hydroponics, from the seeds. Roots from 14 plants at 4 leaves-stage were individually immersed in liquid media contaminated with a suspension of ST isolated from Aterno river in Abruzzo region, Italy (9 log10 cfu/mL final concentration). Two plants were used as negative controls (no ST challenge); surface swabs were taken from leaves and stems to exclude external contaminations. After 24 hours, plants were tested for detection (UNI EN ISO 6579-1:2017) and enumeration (in-house method) of ST in leaves and stems.

Results

ST detection gave positive results in 14/14 plants; in particular, ST was present in 14/14 plants in the leaves and for 9/14 plants also in the stems. The internalized ST strains were also enumerated in 10/14 plants. In particular, 3/14 plants gave positive results both in the leaves and stems, 2/14 only in the stems and other 5/14 only in the leaves. The average ST counts were of 4 log10 cfu/g in leaves and stems. All negative ctr/surface swabs were negative to ST.

Conclusions

Even though antimicrobial properties of basil plants have been described (2), this study demonstrated the potential of ST to internalize, survive and spread to edible parts. The findings highlight the risk of human infections by ST in plant following root uptake, suggesting the importance of applying appropriate preventive pre-harvest strategies.

Biblio

EFSA. E. Jour. (2014);12(3):3600 Tenore et al. (2017). Natural product research, 31(17), 2067-2071

Key messages

The ability of Salmonella Typhimurium to internalize, survive and spread to edible parts of basil plants. Pathogenic bacteria root uptake represents a potential risk for human health.

First report of HEV-3 subtypes e and f in the wild boar population in Abruzzo region, Italy

Background

Hepatitis E virus (HEV) is a zoonotic pathogen and wild boars are recognised as reservoirs. HEV is the most common cause of acute viral hepatitis worldwide and it is usually transmitted by faecal-oral route. EU reported more than 21.000 human cases over the last 10 years (1). At the present, HEV comprises 8 genotypes and several subtypes. HEV genotypes 3 and 4 (HEV-3 and HEV-4) are zoonotic. This is the first report of HEV-3 subtype e and f in the wild boar population in Abruzzo region.

Methods

During the hunting season 2018-2019, liver samples from wild boars were analysed using Real Time RT-PCR for the detection of HEV RNA. Among these, positive sample were subjected to Whole Genome Sequencing for genotyping. After the quality check, reads were mapped using the nearest identified ref. sequence (KU176129) and the resulting HEV RNA sequences have been analysed using HEV net (open source software).

Results

Overall, 40 samples were tested positive for the detection of HEV RNA. Among these, 19 samples, with a Ct value ≤ 38, were selected for phylogenetic analysis. All RNA viral samples belonged to HEV-3. In particular, 2 RNA viral samples belonged to subtype e and 1 to subtype f. The others, instead, belonged to HEV-3 subtype c.

Conclusions

Up to now, only HEV-3 subtype c has been reported among wild boars in Abruzzo, an Italian region officially recognized as an HEV hot spot because of the high number of human cases and for the strong sero-prevalence among blood donors. In this study, we report for the first time the presence of HEV-3 subtypes e and f in the wild boar population of this area. Since HEV-3 subtypes e and f are commonly associated to human disease from consumption of raw/undercooked pork meats, these findings suggest the potential risk also associated with the consumption of wild boar meat. Nevertheless, this speculation needs further investigations.

1.EFSA (2017). Public health risks associated with HEV as a food-borne pathogen. E. Jou., 15(7)

Key messages

First report of the presence of HEV-3 subtypes e and f among wild boar population in Abruzzo region. Potential risk for human health of HEV transmission associated with raw/undercooked wild boar meat consumption.

Campylobacter bacteriophage DA10: an excised temperate bacteriophage targeted by CRISPR-cas

Background

Lytic bacteriophages that infect Campylobacter spp. have been utilized to develop therapeutic/decontamination techniques. However, the association of Campylobacter spp. and bacteriophages has been the focus of several strands of research aimed at understanding the complex relationships that have developed between predators and prey over evolutionary time. The activities of endogenous temperate bacteriophages have been used to evaluate genomic rearrangements and differential protein expression in host cells, and mechanisms of resistance to bacteriophage infection in campylobacters such as phase variation and CRISPR-mediated immunity.

Results

Temperate bacteriophage DA10 represents a novel excised and infective virus capable of replication in a restricted set of C. jejuni and C. coli hosts. Whole genome sequencing reveals that DA10 (35,379 bp) forms part of a novel group of temperate bacteriophages that have limited distribution among database host genome sequences. Analysis of potential host genomes reveals a robust response against DA10 and DA10-like bacteriophages is driven by CRISPR-mediated immunity with 75% of DA10 ORFs represented as ~ 30 bp spacer sequences in numerous Campylobacter Type II-C CRISPR arrays. Several DA10-like homologues have been identified in a small sub-set of C. jejuni and C. coli genome sequences (ranging from near complete integrated prophage sequences to fragments recognisable in the sequence read archive).

Conclusions

A complete intact DA10-like prophage in C. jejuni CJ677CC520 provides evidence that the associations between host and DA10-like bacteriophages are long-standing in evolutionary timescales. Extensive nucleotide substitution and loss can be observed in the integrated DA10-like prophage of CJ677CC520 compared to other relatives as observed through pairwise genome comparisons. Examining factors that have limited the population expansion of the prophage, while others appear to have thrived and prospered (Mu-like, CJIE-like, and lytic Campylobacter bacteriophages) will assist in identifying the underlying evolutionary processes in the natural environment.

Robotic versus laparoscopic approach to treat symptomatic achalasia: systematic review with meta-analysis

Minimally invasive Heller myotomy is considered the gold standard surgical approach for symptomatic achalasia because it is a safe and effective procedure. Over the last years, several studies comparing the laparoscopic and robotic approach for Heller myotomy have been published. Although the robotic approach appears to have some advantages over standard laparoscopy, data on this topic are still controversial and no definite conclusions have been drawn. This metanalysis has been designed to systematically evaluate and compare the effectiveness and safety of the robot-assisted Heller myotomy as compared to the standard laparoscopic approach. According to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, a systematic search on both laparoscopic and robotic Heller myotomy was performed in all the major electronic databases (PubMed, Web of Science, Scopus, EMBASE), using the following search string: (achalasia OR Dor) AND robotic. Six articles were included in the final analysis. A metaregression analysis was performed to assess the possible effects of demographic variables (age, gender, body mass indes (BMI)) and previous abdominal surgery or endoscopic intervention on the analyzed outcomes. No statistical difference was observed in operative times (mean difference (MD) = 20.79, P = 0.19, 95% confidence interval (CI) -10.05,51,62), estimated blood loss (MD = -17.10, P = 0.13, 95% CI -40.48,5.08), conversion rate to open surgery (risk difference (RD) = -0.01, P = 0.33, 95% CI -0.05,0.02), length of hospital stay (MD = -0.73, P = 0.15, 95% CI -1.71,0.25) and long-term recurrence (odds ratio (OR) = 0.59, P = 0.45, 95% CI 0.15,2.33). On the contrary, the robotic approach was found to be associated with a significantly significant lower rate of intraoperative esophageal perforations (OR = 0.13, P < 0.001, 95% CI 0.04, 0.45). Our results suggest that the robotic approach is safer than the laparoscopic Heller myotomy, encouraging the use of robot-assisted surgery. However, our analysis is limited because of the exiguous number of comparative studies and because most of the included studies were statistically underpowered, given the small sample size. Moreover, a high degree of heterogeneity was observed in most of published studies. Taking in consideration the additional costs of robot-assisted procedures, larger Randomized Controlled Trials (RCTs) are advocated to confirm the safety and effectiveness of the robotic approach, and its advantages over standard laparoscopic surgery. In conclusion, well-designed prospective trials and RCTs with homogeneous parameters are needed to draw definitive conclusions about the best surgical approach to pursue in treating symptomatic achalasia.

ABCC Transporters Mediate the Vacuolar Accumulation of Crocins in Saffron Stigmas

Compartmentation is a key strategy enacted by plants for the storage of specialized metabolites. The saffron spice owes its red color to crocins, a complex mixture of apocarotenoid glycosides that accumulate in intracellular vacuoles and reach up to 10% of the spice dry weight. We developed a general approach, based on coexpression analysis, heterologous expression in yeast (Saccharomyces cerevisiae), and in vitro transportomic assays using yeast microsomes and total plant metabolite extracts, for the identification of putative vacuolar metabolite transporters, and we used it to identify Crocus sativus transporters mediating vacuolar crocin accumulation in stigmas. Three transporters, belonging to both the multidrug and toxic compound extrusion and ATP binding cassette C (ABCC) families, were coexpressed with crocins and/or with the gene encoding the first dedicated enzyme in the crocin biosynthetic pathway, CsCCD2. Two of these, belonging to the ABCC family, were able to mediate transport of several crocins when expressed in yeast microsomes. CsABCC4a was selectively expressed in C. sativus stigmas, was predominantly tonoplast localized, transported crocins in vitro in a stereospecific and cooperative way, and was able to enhance crocin accumulation when expressed in Nicotiana benthamiana leaves.plantcell;31/11/2789/FX1F1fx1.

Sterile carbon particle suspension vs India ink for endoscopic tattooing of colonic lesions: a randomized controlled trial

BACKGROUND

Different markers have been used preoperatively to mark colonic lesions, especially India ink. In recent years, another kind of marker has been developed: sterile carbon particle suspension (SCPS). No comparison between these two markers has yet been made. The aim of the present study was to compare the pyrogenic, inflammatory and intraperitoneal effect of these two markers.

METHODS

From September 2015 to December 2018, adult patients who were candidates for elective laparoscopic colon resection were randomized to the SCPS or conventional India ink injection group using computer-based randomization. The primary endpoint of the study was the presence of intraoperative adhesions related to the endoscopic tattoo. Secondary endpoints were differences in white blood cell, C-reactive protein, and fibrinogen levels as well as, abdominal pain and body temperature at baseline (before endoscopic tattooing) and 6 and 24 h after colonoscopy. Finally, the visibility of the tattoo during the minimally invasive intervention was assessed.

RESULTS

Ninety-four patients were included in the study, 47 for each arm. There were 45/94 females (47.9%) and 49/94 males (52.1%), with a median age of 67.85 ± 9.22 years. No differences were found between groups in WBC, fibrinogen levels, body temperature or VAS scores, but we documented significantly higher CRP values at 6 and 24 h after endoscopic tattooing with India ink injection. There were significantly fewer adhesions in the SCPS Endoscopic Marker group. All the endoscopic tattoos were clearly visible.

CONCLUSIONS

SCPS is an effective method for tattooing colonic lesions and has a better safety profile than traditional India ink in terms of post-procedure inflammatory response and intraoperative bowel adhesions.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov (ID: NCT03637933).

A chromosome-anchored eggplant genome sequence reveals key events in Solanaceae evolution

With approximately 450 species, spiny Solanum species constitute the largest monophyletic group in the Solanaceae family, but a high-quality genome assembly from this group is presently missing. We obtained a chromosome-anchored genome assembly of eggplant (Solanum melongena), containing 34,916 genes, confirming that the diploid gene number in the Solanaceae is around 35,000. Comparative genomic studies with tomato (S. lycopersicum), potato (S. tuberosum) and pepper (Capsicum annuum) highlighted the rapid evolution of miRNA:mRNA regulatory pairs and R-type defense genes in the Solanaceae, and provided a genomic basis for the lack of steroidal glycoalkaloid compounds in the Capsicum genus. Using parsimony methods, we reconstructed the putative chromosomal complements of the key founders of the main Solanaceae clades and the rearrangements that led to the karyotypes of extant species and their ancestors. From 10% to 15% of the genes present in the four genomes were syntenic paralogs (ohnologs) generated by the pre-γ, γ and T paleopolyploidy events, and were enriched in transcription factors. Our data suggest that the basic gene network controlling fruit ripening is conserved in different Solanaceae clades, and that climacteric fruit ripening involves a differential regulation of relatively few components of this network, including CNR and ethylene biosynthetic genes.

Single Primer Enrichment Technology (SPET) for High-Throughput Genotyping in Tomato and Eggplant Germplasm

Single primer enrichment technology (SPET) is a new, robust, and customizable solution for targeted genotyping. Unlike genotyping by sequencing (GBS), and like DNA chips, SPET is a targeted genotyping technology, relying on the sequencing of a region flanking a primer. Its reliance on single primers, rather than on primer pairs, greatly simplifies panel design, and allows higher levels of multiplexing than PCR-based genotyping. Thanks to the sequencing of the regions surrounding the target SNP, SPET allows the discovery of thousands of closely linked, novel SNPs. In order to assess the potential of SPET for high-throughput genotyping in plants, a panel comprising 5k target SNPs, designed both on coding regions and introns/UTRs, was developed for tomato and eggplant. Genotyping of two panels composed of 400 tomato and 422 eggplant accessions, comprising both domesticated material and wild relatives, generated a total of 12,002 and 30,731 high confidence SNPs, respectively, which comprised both target and novel SNPs in an approximate ratio of 1:1.6, and 1:5.5 in tomato and eggplant, respectively. The vast majority of the markers was transferrable to related species that diverged up to 3.4 million years ago (Solanum pennellii for tomato and S. macrocarpon for eggplant). Maximum Likelihood phylogenetic trees and PCA outputs obtained from the whole dataset highlighted genetic relationships among accessions and species which were congruent with what was previously reported in literature. Better discrimination among domesticated accessions was achieved by using the target SNPs, while better discrimination among wild species was achieved using the whole SNP dataset. Our results reveal that SPET genotyping is a robust, high-throughput technology for genetic fingerprinting, with a high degree of cross-transferability between crops and their cultivated and wild relatives, and allows identification of duplicates and mislabeled accessions in genebanks.

Pivotal Roles of Cryptochromes 1a and 2 in Tomato Development and Physiology

Cryptochromes are flavin-containing blue/UVA light photoreceptors that regulate various plant light-induced physiological processes. In Arabidopsis (Arabidopsis thaliana), cryptochromes mediate de-etiolation, photoperiodic control of flowering, entrainment of the circadian clock, cotyledon opening and expansion, anthocyanin accumulation, and root growth. In tomato (Solanum lycopersicum), cryptochromes are encoded by a multigene family, comprising CRY1a, CRY1b, CRY2, and CRY3 We have previously reported the phenotypes of tomato cry1a mutants and CRY2 overexpressing plants. Here, we report the isolation by targeting induced local lesions in genomes, of a tomato cry2 knock-out mutant, its introgression in the indeterminate Moneymaker background, and the phenotypes of cry1a/cry2 single and double mutants. The cry1a/cry2 mutant showed phenotypes similar to its Arabidopsis counterpart (long hypocotyls in white and blue light), but also several additional features such as increased seed weight and internode length, enhanced hypocotyl length in red light, inhibited primary root growth under different light conditions, anticipation of flowering under long-day conditions, and alteration of the phase of circadian leaf movements. Both cry1a and cry2 control the levels of photosynthetic pigments in leaves, but cry2 has a predominant role in fruit pigmentation. Metabolites of the sterol, tocopherol, quinone, and sugar classes are differentially accumulated in cry1a and cry2 leaves and fruits. These results demonstrate a pivotal role of cryptochromes in controlling tomato development and physiology. The manipulation of these photoreceptors represents a powerful tool to influence important agronomic traits such as flowering time and fruit quality.

The applications of bacteriophages and their lysins as biocontrol agents against the foodborne pathogens Listeria monocytogenes and Campylobacter: An updated look

Listeria monocytogenes and Campylobacter spp. are foodborne pathogens responsible for outbreaks and disease in humans. The emerging problem of bacterial antibiotic resistance and the persistence of pathogens in the environment, especially where foods are processed, are some of the reasons that have led to a re‑emerging interest in bacteriophages and their lysins as potential candidates for bio‑control. This review focuses on the use of bacteriophages and their lysins as alternative strategies for controlling the foodborne pathogens L. monocytogenes and Campylobacter spp. In addition, the application of bacteriophages and their lysins in food safety and animal health, as well as phage‑resistance development, legislation, and future prospects were discussed.

Candidate Enzymes for Saffron Crocin Biosynthesis Are Localized in Multiple Cellular Compartments

Saffron is the dried stigmas of Crocus sativus and is the most expensive spice in the world. Its red color is due to crocins, which are apocarotenoid glycosides that accumulate in the vacuole to a level up to 10% of the stigma dry weight. Previously, we characterized the first dedicated enzyme in the crocin biosynthetic pathway, carotenoid cleavage dioxygenase2 (CsCCD2), which cleaves zeaxanthin to yield crocetin dialdehyde. In this work, we identified six putative aldehyde dehydrogenase (ALDH) genes expressed in C. sativus stigmas. Heterologous expression in Escherichia coli showed that only one of corresponding proteins (CsALDH3I1) was able to convert crocetin dialdehyde into the crocin precursor crocetin. CsALDH3I1 carries a carboxyl-terminal hydrophobic domain, similar to that of the Neurospora crassa membrane-associated apocarotenoid dehydrogenase YLO-1. We also characterized the UDP-glycosyltransferase CsUGT74AD1, which converts crocetin to crocins 1 and 2'. In vitro assays revealed high specificity of CsALDH3I1 for crocetin dialdehyde and long-chain apocarotenals and of CsUGT74AD1 for crocetin. Following extract fractionation, CsCCD2, CsALDH3I1, and CsUGT74AD1 were found in the insoluble fraction, suggesting their association with membranes or large insoluble complexes. Analysis of protein localization in both C. sativus stigmas and following transgene expression in Nicotiana benthamiana leaves revealed that CsCCD2, CsALDH3I, and CsUGT74AD1 were localized to the plastids, the endoplasmic reticulum, and the cytoplasm, respectively, in association with cytoskeleton-like structures. Based on these findings and current literature, we propose that the endoplasmic reticulum and cytoplasm function as transit centers for metabolites whose biosynthesis starts in the plastid and are accumulated in the vacuole.

Agrobacterium-mediated and electroporation-mediated transformation of Chlamydomonas reinhardtii: a comparative study

Background

Chlamydomonas reinhardtii is an unicellular green alga used for functional genomics studies and heterologous protein expression. A major hindrance in these studies is the low level and instability of expression of nuclear transgenes, due to their rearrangement and/or silencing over time.

Results

We constructed dedicated vectors for Agrobacterium-mediated transformation carrying, within the T-DNA borders, the Paromomycin (Paro) selectable marker and an expression cassette containing the Luciferase (Luc) reporter gene. These vectors and newly developed co-cultivation methods were used to compare the efficiency, stability and insertion sites of Agrobacterium- versus electroporation-mediated transformation. The influence of different transformation methods, of the cell wall, of the virulence of different Agrobacterium strains, and of transgene orientation with respect to T-DNA borders were assessed. False positive transformants were more frequent in Agrobacterium-mediated transformation compared to electroporation, compensating for the slightly lower proportion of silenced transformants observed in Agrobacterium-mediated transformation than in electroporation. The proportion of silenced transformants remained stable after 20 cycles of subculture in selective medium. Next generation sequencing confirmed the nuclear insertion points, which occurred in exons or untraslated regions (UTRs) for 10 out of 10 Agrobacterium-mediated and 9 out of 13 of electroporation-mediated insertions. Electroporation also resulted in higher numbers of insertions at multiple loci.

Conclusions

Due to its labor-intensive nature, Agrobacterium transformation of Chlamydomonas does not present significant advantages over electroporation, with the possible exception of its use in insertional mutagenesis, due to the higher proportion of within-gene, single-locus insertions. Our data indirectly support the hypothesis that rearrangement of transforming DNA occurs in the Chlamydomonas cell, rather than in the extracellular space as previously proposed.

Electronic supplementary material

The online version of this article (10.1186/s12896-018-0416-3) contains supplementary material, which is available to authorized users.

Multiplex PCR to detect bacteriophages from natural whey cultures of buffalo milk and characterisation of two phages active against Lactococcus lactis, ΦApr-1 and ΦApr-2

This work investigated bacteriophage induced starter failures in artisanal buffalo Mozzarella production plants in Southern Italy. Two hundred and ten samples of whey starter cultures were screened for bacteriophage infection. Multiplex polymerase chain reaction (PCR) revealed phage infection in 28.56% of samples, all showing acidification problems during cheese making. Based on DNA sequences, bacteriophages for Lactococcus lactis (L. lactis), Lactobacillus delbruekii (L. delbruekii) and Streptococcus thermophilus (S. thermophilus) were detected. Two phages active against L. lactis, ΦApr-1 and ΦApr-2, were isolated and characterised. The genomes, approximately 31.4 kb and 31 kb for ΦApr-1 and ΦApr-2 respectively, consisted of double-stranded linear DNA with pac-type system. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‑PAGE) showed one major structural protein of approximately 32.5 kDa and several minor proteins. This is the first report of phage isolation in buffalo milk and of the use of multiplex PCR to screen and study the diversity of phages against Lactic Acid Bacteria (LAB) strains in artisanal Water Buffalo Mozzarella starters.

Population Diversity of Campylobacter jejuni in Poultry and Its Dynamic of Contamination in Chicken Meat

This study aimed to analyse the diversity of the Campylobacter jejuni population in broilers and to evaluate the major source of contamination in poultry meat. Eight rearing cycles over one year provided samples from three different broiler farms processed at the same slaughterhouse. A total of 707 C. jejuni were isolated from cloacal swabs before slaughter and from the breast skin of carcasses after slaughter and after chilling. All suspected Campylobacter colonies were identified with PCR assays and C. jejuni was genotyped by sequence analysis of the flaA short variable region (SVR) and by pulsed-field gel electrophoresis (PFGE) using SmaI enzyme. Phenotypic antibiotic resistance profiles were also assayed using minimal inhibitory concentration (MIC). The flocks carried many major C. jejuni clones possibly carrying over the rearing cycles, but cross contamination between farms may happen. Many isolates were resistant to fluoroquinolones, raising an issue of high public concern. Specific Campylobacter populations could be harboured within each poultry farm, with the ability to contaminate chickens during each new cycle. Thus, although biosecurity measures are applied, with a persistent source of contamination, they cannot be efficient. The role of the environment needs further investigation to better address strategies to control Campylobacter.

A draft genome sequence of an invasive mosquito: an Italian Aedes albopictus

The draft genome sequence of Italian specimens of the Asian tiger mosquito Aedes (Stegomyia) albopictus (Diptera: Culicidae) was determined using a standard NGS (next generation sequencing) approach. The size of the assembled genome is comparable to that of Aedes aegypti; the two mosquitoes are also similar as far as the high content of repetitive DNA is concerned, most of which is made up of transposable elements. Although, based on BUSCO (Benchmarking Universal Single-Copy Orthologues) analysis, the genome assembly reported here contains more than 99% of protein-coding genes, several of those are expected to be represented in the assembly in a fragmented state. We also present here the annotation of several families of genes (tRNA genes, miRNA genes, the sialome, genes involved in chromatin condensation, sex determination genes, odorant binding proteins and odorant receptors). These analyses confirm that the assembly can be used for the study of the biology of this invasive vector of disease.

The coffee genome provides insight into the convergent evolution of caffeine biosynthesis

Coffee is a valuable beverage crop due to its characteristic flavor, aroma, and the stimulating effects of caffeine. We generated a high-quality draft genome of the species Coffea canephora, which displays a conserved chromosomal gene order among asterid angiosperms. Although it shows no sign of the whole-genome triplication identified in Solanaceae species such as tomato, the genome includes several species-specific gene family expansions, among them N-methyltransferases (NMTs) involved in caffeine production, defense-related genes, and alkaloid and flavonoid enzymes involved in secondary compound synthesis. Comparative analyses of caffeine NMTs demonstrate that these genes expanded through sequential tandem duplications independently of genes from cacao and tea, suggesting that caffeine in eudicots is of polyphyletic origin.

Characterization of antimicrobial resistance patterns and detection of virulence genes in Campylobacter isolates in Italy

Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations.

Escherichia coli, Salmonella spp., Hepatitis A virus and norovirus in bivalve molluscs in Southern Italy

European Legislation has fixed microbiological, chemical and biotoxicological limits for shellfish but no limits for viruses. In the present study we report the results of an investigation on Salmonella spp., Escherichia coli, Hepatitis A virus (HAV) and Norovirus (NoV) contamination in 59 bivalve shellfish collected during the years 2011-2012 in Southern Italy. All the samples of Mytilus galloprovincialis and of Solen marginatus were negative for HAV whereas 6.8% of them were positive for Norovirus GI (NoVGI) and 11.9% positive for Norovirus GII (NoVGII). Samples were also negative for Salmonella spp., while 16 of them (27%) were positive for E. coli. No correlation was found between E. coli and NoV contamination in bivalve molluscs. Moreover, the Competent Authorities are advised to take into serious consideration additional measures for the legislation in force in order to guarantee the consumer's health.

Occurrence of G-banding in metaphase chromosomes of Encarsia berlesei (Hymenoptera: Aphelinidae)

Well-defined G-bands were obtained on somatic metaphase chromosomes of Encarsia berlesei using trypsin and warm 2x SCC in sequence. The G-banded pattern allowed rapid identification of all five metacentric chromosomes, which appeared uniformly lighted when stained with DAPI fluorochrome dye. It is stressed that ageing affects G-banding in this insect species; in fact, good banded chromosomes were obtained on 1-month air-stored chromosomes. Evidence for asynchronous condensation on the chromosomes of this species is also provided.

Prokinetic effect of a standardized yarrow (Achillea millefolium) extract and its constituent choline: studies in the mouse and human stomach

BACKGROUND

Functional dyspepsia (FD) is a highly prevalent gastrointestinal disorder characterized by alterations in gastric motility. Yarrow (Achillea millefolium L., Fam Asteraceae) preparations are traditional remedies used to treat dyspeptic complaints. Herein, we investigated the effect of a standardized dry water extract obtained from A. millefolium flowering tops (AME) on gastric motility.

METHODS

The effect of AME on motility was evaluated on the resting tone of the isolated gastric antrum and on gastric emptying in vivo (phenol red meal method) both in control mice and in the model of cancer chemotherapy (cisplatin)-induced gastric abnormalities.

KEY RESULTS

The AME contracted mouse and human gastric strips and this action was unaffected by hexamethonium and tetrodotoxin, but strongly reduced by atropine. Among various chemical ingredients in yarrow, choline, but not the flavonoids rutin and apigenin, mimicked the action of AME. Furthermore, AME deprived of choline did not exert a contractile effect. In vivo, AME stimulated gastric emptying both in control and in cisplatin-treated mice, being more active in pathological states.

CONCLUSIONS & INFERENCES

It is concluded that (i) AME exerts a direct spasmogenic effect on gastric antrum; (ii) choline is the chemical ingredient responsible of such effect; (iii) the prokinetic effect of AME observed in vivo could provide the pharmacological basis underlying its traditional use in the treatment of dyspepsia.

Proinflammatory stimuli activates human-derived enteroglial cells and induces autocrine nitric oxide production

BACKGROUND

Enteric glial cells (EGCs) have been recently indicated as key regulators of intestinal inflammation in animals. Whether or not this is true and how these cells participate to inflammatory responses in humans is unknown.

METHODS

We isolated primary EGCs from human small bowel and then, we purified and characterized those using specific glial markers, such as S100B and glial fibrillary acidic protein (GFAP). To mimic an inflammatory scenario, we exposed EGCs to exogenous stimuli, such as lipopolysaccharide and interferon-gamma (LPS and IFN-γ), alone or in combination, to evaluate glial activation [measuring GFAP, S100B level together with c-fos, major histocompatibility complex (MHC) class II, inducible nitric oxide (iNOS) proteins expression and nitric oxide (NO) production] and proliferation, respectively.

KEY RESULTS

We showed that, when challenged with a combination of LPS and IFN-γ, EGCs are significantly activated, as indicated by their positivity to c-fos and MHC class II. Similarly, pro-inflammatory stimuli significantly increase the cell proliferation rate, the expression of both S100B and GFAP, and the NO production consequent to the induction of EGCs-derived iNOS protein, with the last being dependent on S100B-RAGE (receptor for advanced glycation endproducts) interaction.

CONCLUSIONS & INFERENCES

Our data provide the first evidence that human EGCs directly respond to pro-inflammatory stimuli by changing their expression profile and by proliferating. The finding that stimulated EGCs are able to produce NO points to a role of this cell population in the scenario of intestinal inflammation.

Characterisation of bubaline coronavirus strains associated with gastroenteritis in water buffalo (Bubalus bubalis) calves

Recently, a coronavirus strain (179/07-11) was isolated from water buffalo (Bubalus bubalis) and the virus which displayed a strict genetic and biological relatedness with bovine coronavirus (BCoV) was referred to as bubaline coronavirus (BuCoV). Here, we report the characterisation of four BuCoVs strains identified in the faeces or intestinal contents of water buffalo calves with acute gastroenteritis. Single BuCoV infections were detected in all but one cases from which two clostridia species were also isolated. Sequence and phylogenetic analyses of the 5' end of the spike-protein gene showed that three BuCoVs were closely related to the prototype strain 179/07-11, whereas the fourth isolate (339/08-C) displayed a higher genetic identity to recent BCoV reference strains. Three strains adapted to the in vitro grow on human rectal tumour cells were also evaluated for their ability to replicate in a bovine cell line (Madin Darby bovine kidney) and to cause haemagglutination of chicken erythrocytes and all displayed biological properties similar to those already described for the prototype BuCoV. The present report shows that albeit genetically heterogeneous, the different BuCoV strains possess a common biological pattern which is different from most BCoV and BCoV-like isolates.

Cytological evidence for population-specific sex chromosome heteromorphism in Palaearctic green toads (Amphibia, Anura)

A chromosome study was carried out on a number of European and Central Asiatic diploid green toad populations by means of standard and various other chromosome banding and staining methods (Ag-NOR-, Q-, CMA3-, late replicating [LR] banding pattern, C-and sequential C-banding + CMA3 + DAPI). This study revealed the remarkable karyological uniformity of specimens from all populations, with the only exception being specimens from a Moldavian population, where one chromosome pair was heteromorphic. Though similar in shape, size and with an identical heterochromatin distribution,the difference in the heteromorphic pair was due to a large inverted segment on its long arms. This heteromorphism was restricted to females, suggesting a female heterogametic sex chromosome system of ZZ/ZW type at a very early step of differentiation.

[Surgical treatment and prognostic factors in colorectal cancer]

AIM

The aim of this study was to make a contribution to improve the care of patients with colorectal cancer by optimizing times and methods of the follow-up; particular attention is given to factors which may be important for the prognosis and for the quality of life in the immediate postoperative period.

METHODS

The study includes all the patients with colorectal cancer who underwent laparotomic surgical treatment from 1996 to 2003. The total number of patients was 226 with an average age of 65 years; male to female ratio was 1.57:1. According to the stage of tumor, an adjuvant radiotherapeutic and/or chemiotherapeutic treatment was associated to surgery.

RESULTS

On the basis of the preoperative staging and tumor localization, our patients underwent: 3 total colectomies, 57 right hemicolectomies, 137 left hemicolectomies, 6 Hartmann resections, 19 Miles resections, 4 transverse resections.

CONCLUSION

The results obtained show that the 5-year overall survival is particularly influenced by the stage and the factors which directly or indirectly affect the primary tumor; thus the prognostic factors which should be considered for the survival and in the follow-up of these patients are: stage, grading and nodal involvement of the tumor.

Karyology of the Antarctic scallop Adamussium colbecki, with some comments on the karyological evolution of pectinids

Karyotype, location of the nucleolar organiser region (NOR) and heterochromatin presence and composition were studied in the Antarctic scallop Adamussium colbecki Smith, 1902. The karyotype exhibits 2n = 38 chromosomes with 11 pairs of metacentrics, 5 of submetacentrics, one subtelocentric and two telocentrics. Ag-NOR, CMA(3), DA/MM and NOR-FISH evidenced paracentromeric NORs on the short arm of 2nd pair chromosomes. Digestion with three restriction endonucleases followed by sequential staining with Giemsa, CMA(3) and DAPI evidenced on all chromosomes centromeric heterochromatin positive for both DAPI and CMA(3). In situ hybridisation analysis showed the presence of an AT-rich satellite DNA in the centromeric heterochromatin of several chromosomes. A mosaicism was detected in the germinal cell lines of one specimen, as in six of the 20 plates examined the set had 37 chromosomes with a missing pair of telocentrics and an unpaired metacentric. Comparison of the chromosome sets of all the pectinids studied to date and comparison with a phyletic tree obtained from molecular mitochondrial genes studies yielded good agreement between karyotype morphology and taxonomic classification.

[Ultrasound-guided endoscopic drainage, without radiological examination, in patients with neoplastic biliary obstruction. Preliminary results]

AIM

Endoscopic stent insertion has become the preferred method for palliation of malignant biliary obstruction. Currently, endoscopic stent placement involves the use of contrast media and radiological equipment to achieve direct opacification of the biliary duct systems, and to determine the location and the extension of biliary obstruction. This report proposes a new combination of ultrasonography and biliary endoscopy, with endoscopic stent placement entirely performed under US-guidance.

METHODS

US-guided stent placement was carried out in 8 patients. A guide-wire and a guiding-catheter were endoscopically introduced and identified, by US, the common bile duct across the stricture. Hydromer-coated polyurethane angled stents (10F) were finally inserted over the guide-wire/guiding-catheter by a pusher tube system.

RESULTS

Successful stent insertion was achieved in all patients. There were no complications. Successful drainage, with substantial reduction in bilirubin level, was achieved in all patients (14.2+/-9.5 vs 4.2+/-2.9 mg/dl at 1 week).

CONCLUSION

Endoscopic stent placement performed under US-guidance, is safe and effective. Further studies in a larger series, including more proximal strictures are suggested.

Cytological and molecular analysis in the rare discoglossid species, Alytes muletensis (Sanchiz & Adrover 1977) and its bearing on archaeobatrachian phylogeny

Cytogenetic and molecular data on Alytes muletensis (Amphibia: Discoglossidae) are compared with other representatives of archaeobatrachian frogs: Bombina variegata pachypus, Pelobates cultripes, Pelodytes punctatus, Xenopus laevis, and Discoglossus. A. muletensis has the karyotype typical for the genus Alytes, 38 elements with either one or two arms, some of which can be considered as 'microchromosomes'. The NORs are located on the telomeres of the tenth chromosome pair which agrees with the state in A. obstetricians but differs from A. cisternasii reflecting phylogenetic affinities. C-banding and staining with DAPI and chromomycin A3 revealed important blocks of telomeric CMA-positive heterochromatin on the smaller chromosomes of Alytes, similar to the state found in Discoglossus. Phylogenetic analysis of 750 bp of fragments of the mitochondrial 16S and 12S rRNA genes corroborated that Discoglossus and Alytes are sister taxa which together probably form the sister group of the Bombinatorinae. Centromeric heterochromatin in Alytes may be responsible for the retention of a plesiomorphic asymmetric karyotype which independently has evolved into a symmetric karyotype through centric fusions in Bombina and Discoglossus. The HindIII satellite DNA family was present in all archaeobatrachians studied but absent in hyloid and ranoid neobatrachians.

Role of surgery in thymic disorders

Thymomas are relatively slow-growing neoplasms that should be considered malignant tumours. When treated in the early stages, however, they have an excellent prognosis for long-term survival. Surgery, radiation therapy and chemotherapy all play a role in the management of these neoplasms. Surgery is the treatment of choice in thymoma patients and has become an increasingly accepted procedure in the treatment of myasthenia gravis (MG) since 1936, when thymectomy was performed for this disease for the first time. Improvement in myasthenic symptoms is nearly always observed following thymectomy, but the rates of complete remission vary from 7% to 63%. We have studied the potential preoperative factors predicting the evolution of MG.

[Aneurysms of the splanchnic arteries]

Although visceral aneurysms usually have an asymptomatic course, ruptures associated with high mortality do occur. When an asymptomatic lesion is found, the physician must decide whether it should be treated surgically and which surgical technique should be used. Because this type of aneurysm is relatively rare, the answer to these questions have not been determined previously. The outcome in 16 patients treated by surgical or embolization procedures was evaluated. A group of 16 patients with visceral aneurysms were observed in our institution between 1987 and 1993. Localization of aneurysms was on the splenic artery in 8 cases, renal artery in 4 cases, hepatic artery in 3 patients and superior mesenteric artery in one patient. Hypertension was related to renal aneurysms and angina abdominis to the patient with superior mesenteric artery aneurysm. Of the 16 patients, 8 (6 splenic and 2 hepatic aneurysms) were asymptomatic, 3 (2 splenic and 1 hepatic) were treated as an emergency because they presented with shock. In the splenic group (8 cases), 2 patients underwent embolization procedures with Gianturco's coils, and 6 surgical procedures; in the hepatic group 1 embolization and 1 surgical procedure were performed; and finally in the renal and mesenteric group surgical reconstruction was performed during aortic prosthetic surgery. Because of well documented natural history of progressive enlargement and eventual rupture, the aneurysms of visceral arteries should be corrected surgically when the diagnosis is confirmed by vascular imaging (ultrasounds, CT, RM, angiography). Ruptures are treated with emergency operations, when possible. In high-risk patients, non operative management by selective embolization (in case of splenic and hepatic aneurysms) may be suitable alternative.