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Aging is accompanied by the progressive decline in tissue regenerative capacity and functions of resident stem cells (SCs). Underlying mechanisms, however, remain unclear. Here we show that, during chronological aging, self-renewing mitoses of mammary SCs (MaSCs) are preferentially asymmetric and that their progeny divides less frequently, leading to decreased number of MaSCs and reduced regenerative potential. Underlying mechanisms are investigated in the p66Shc

MYC is a key oncogenic driver and an adverse prognostic factor in multiple types of cancer, including diffuse large B-cell lymphoma (DLBCL). Yet, MYC activation also endows cancer cells with a series of metabolic dependencies, which can provide strategic points for targeted pharmacological intervention. We recently reported that targeting the mitochondrial electron transport chain (ETC) complex I with the small molecule inhibitor IACS-010759 selectively killed MYC-overexpressing lymphoid cells. Here, we unravel the mechanistic basis for this synthetic-lethal interaction and exploit it to improve the anti-tumoral effects of ETC inhibition. In a mouse B-cell line, MYC hyperactivation and IACS-010759 treatment added up to induce oxidative stress, with consequent depletion of reduced glutathione and lethal disruption of redox homeostasis. This effect could be enhanced by targeted pharmacological intervention, with either inhibitors of NADPH production through the pentose phosphate pathway, or with ascorbate (vitamin C), known to contribute pro-oxidant effects when administered at high doses. In these conditions, ascorbate synergized with IACS-010759 to kill MYC-overexpressing cells in vitro and reinforced its therapeutic action against human B-cell lymphoma xenografts. Hence, ETC inhibition and high-dose ascorbate might improve the outcome of patients affected by high-grade lymphomas and other MYC-driven cancers.Key point #1MYC and the ETC complex I inhibitor IACS-010759 elicit different reactive oxygen species (ROS) that cooperate to disrupt redox homeostasis.Key point #2Further boosting of oxidative stress with high doses of ascorbate increases the killing of MYC-driven lymphoma xenografts by IACS-010759.

Cystic fibrosis (CF) is a hereditary disease due to mutations in the CFTR gene and causes mortality in humans mainly due to respiratory infections caused by Pseudomonas aeruginosa. In a previous work we used phage therapy, which is a treatment with a mix of phages, to actively counteract acute P. aeruginosa infections in mice and Galleria mellonella larvae. In this work we apply phage therapy to the treatment of P. aeruginosa PAO1 infections in a CF zebrafish model. The structure of the CFTR channel is evolutionary conserved between fish and mammals and cftr-loss-of-function zebrafish embryos show a phenotype that recapitulates the human disease, in particular with destruction of the pancreas. We show that phage therapy is able to decrease lethality, bacterial burden, and the pro-inflammatory response caused by PAO1 infection. In addition, phage administration relieves the constitutive inflammatory state of CF embryos. To our knowledge, this is the first time that phage therapy is used to cure P. aeruginosa infections in a CF animal model. We also find that the curative effect against PAO1 infections is improved by combining phages and antibiotic treatments, opening a useful therapeutic approach that could reduce antibiotic doses and time of administration.

The sweet chestnut (Castanea sativa Mill.) is an important species of European trees, studied for both ecological and economic reasons. Its cultivation in the Italian peninsula can be linked to the Roman period and has been documented, especially in the Tuscan region, for centuries. We sampled 131 grafted trees from three separate areas to determine the genetic variability between populations and assess genetic identity for different varieties of trees, which is useful for future breeding programs and propagation efforts. Molecular analyses were performed using eight microsatellite loci. A total of 98 alleles was detected with an average of 12.3 alleles per locus. We found high levels of genetic diversity within the varieties of the same area, ranging between He = 0.682–0.745. Of the eight loci, seven were found to be at Hardy-Weinberg equilibrium. (FST values Differentiation between cultivation areas was significant between 0.052–0.147) with the two Southern Tuscan areas showing the closest relationship as also indicated by Bayesian inference of the population structure, which revealed the existence of three ancestral gene pools of origin. Demographic events were detected by a coalescent-based approximate Bayesian computation in two of the homogeneous clusters. This work is a step forward for the conservation of this iconic species, albeit at a regional level, as chestnut varieties have never received the full attention of breeders.

Hair analysis is an important and reliable resource for the assessment of alcohol or drug abstinence in both clinical and forensic toxicology. Recently, it has been demonstrated that hair oxidative cosmetic treatments lead to the reduction in incorporated xenobiotics in hair, such as ethyl glucuronide (EtG), a marker of alcohol abuse, and the formation of 1-H-pyrrole-2,3,5-tricarboxylic acid (PTCA), a degradation product of melanin. The aim of the present study was to investigate PTCA trends in a large number of samples in order to evaluate the reliability of this biomarker in recognizing previous cosmetic treatment in forensic analyses. Therefore, a single-step extraction followed by an high-performance liquid chromatography--tandem mass spectrometry (HPLC--MS-MS) method was established and validated for the simultaneous determination of EtG and PTCA. This method was applied to 1,219 scalp hair samples from two groups, namely self-reported untreated and in vivo treated hair, exhibiting a concentration range of 6.7 to 440.0 pg/mg for EtG (mean 26.8 pg/mg, median 14.6 pg/mg) and 0.009 to 49.8 ng/mg for PTCA (mean 0.66 ng/mg, median 0.02 ng/mg). The PTCA content was significantly different among the two experimental groups, with the in vivo treated group showing significantly higher levels of PTCA than the untreated group. Finally, an in vitro bleaching was performed and the results confirmed that a strong hair oxidative treatment may negatively affect EtG test results (false negative), whereas the mean PTCA content increased showing statistically significant differences between untreated and in vitro oxidative treated samples. The present study suggests that the determination of PTCA in routine hair analysis procedure could be useful in order to discover previous cosmetic treatment including oxidation.

Cannabis products rich in cannabidiol (CBD) and low in Δ9-tetrahydrocannabinol (THC) (e.g., light cannabis in Italy) are becoming widely popular and available on the market as replacements for THC preparations and tobacco for their recreational and/or therapeutic benefits. In this paper, which aims to establish alternative discrimination parameters between hair samples from CBD-rich and THC-prevalent cannabis users, cannabinoid concentrations, such as THC, CBD, 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) and 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) were quantified in 127 hair samples by a GC-MS/MS technique. Initially, this analysis was able to discriminate two cohorts: cohort 1 (individuals with THC values ≥ 0.05 ng/mg and THC-COOH ≥ 0.2 pg/mg or THC-positive users, n = 60) and cohort 2 (individuals with THC values ranging between 0.01 and 0.05 ng/mg and THC-COOH or 11-OH-THC ≥ LOQs, n = 67). The evaluation of CBD/THC ratio in cohort 2 identified two further sub-cohorts 2a (CBD/THC1 or ~ 1, THC-prevalent cannabis users) and 2b (CBD/THC1, suspected CBD-rich and THC-low cannabis users). The latter showed unusual profiles for THC metabolites, in particular for 11-OH-THC. Statistical evaluation of the data of cohort 1, cohort 2a and cohort 2b yielded significant differences in CBD/THC and THC/11-OH-THC. Based on the analysis of 337 seized cannabis samples and 630 CBD-rich/light cannabis samples by GC-FID and GC-MS, respectively, we also evaluated statistical differences in the CBD/THC ratio between biological (hair) and plant-derived samples. Considering the legal implications of a positive result, the obtained findings could be relevant for the interpretation of cannabinoid concentrations in hair. Further studies are necessary to elucidate the reason behind the unusual metabolic ratios.

Phylogenetic patterns and the underlying speciation processes can be deduced from morphological, functional, and ecological patterns of species similarity and divergence. In some cases, though, species retain multiple similarities and remain almost indistinguishable; in other cases, evolutionary convergence can make such patterns misleading; very often in such cases, the “true” picture only emerges from carefully built molecular phylogenies, which may come with major surprises. In addition, closely related species may experience gene flow after divergence, thus potentially blurring species delimitation. By means of advanced inferential methods, we studied molecular divergence between species of the Virola genus (Myristicaceae): widespread Virola michelii and recently described, endemic V. kwatae, using widespread V. surinamensis as a more distantly related outgroup with different ecology and morphology—although with overlapping range. Contrary to expectations, we found that the latter, and not V. michelii, was sister to V. kwatae. Therefore, V. kwatae probably diverged from V. surinamensis through a recent morphological and ecological shift, which brought it close to distantly related V. michelii. Through the modeling of the divergence process, we inferred that gene flow between V. surinamensis and V. kwatae stopped soon after their divergence and resumed later, in a classical secondary contact event which did not erase their ecological and morphological differences. While we cannot exclude that initial divergence occurred in allopatry, current species distribution and the absence of geographical barriers make complete isolation during speciation unlikely. We tentatively conclude that (a) it is possible that divergence occurred in allopatry/parapatry and (b) secondary contact did not suppress divergence., We studied molecular divergence between species of the Neotropical Virola genus: widespread Virola michelii and recently described, endemic V. kwatae, using widespread V. surinamensis as a more distantly related outgroup with different ecology and morphology—although with overlapping range. We found that the latter, and not V. michelii, is sister to V. kwatae. This partial reassessment of the phylogeny in the Virola genus led us to investigate and to assess, by using coalescent theory and Bayesian modelling, the presence of gene flow after speciation in the pair V. kwatae/V. surinamensis, indicating the existence of phylogenetic radiation without strict reproductive isolation.

Recent evidence suggests that 2-week treatment with the non-psychotomimetic cannabinoid cannabidivarin (CBDV) could be beneficial towards neurological and social deficits in early symptomaticThe aim of this study was to provide further insights into the efficacy of CBDV inCBDV 0.2, 2, 20 and 200 mg/kg/day was administered toCBDV rescues recognition memory deficits inCBDV administration exerts an enduring rescue of memory deficits in

The potential effects of climate change on the distribution of Mediterranean plants at their peripheral range make them extremely vulnerable to environmental fluctuations. The northern-most Italian population of Cistus albidus provides an outstanding case for study, as it grows at the extreme northern edge of its range and because phenological data have been available since the early XIX century. In the period 2012–2017, we analysed the population demography and spatial structure, growth and flowering phenology, and genetic variability to understand the history, current state and possible evolution of this population. Lastly, the population data were tested for association with environmental factors. The population studied consists of plants on average 10 years old, showing the highest growth rates in spring and autumn. Anthesis starts in April and ends in early June and is significantly dependent on temperature. High levels of genetic variability are present (average He = 0.471), with heterozygote excess detected at four loci out of five. Bayesian analysis does not support any genetic structuring of the population. The aggregated pattern in the distribution of individuals and their phenological traits, together with the absence of genetic structuring, seem to suggest that this extreme geographical population is not currently endangered.

Background: Recent evidence suggests that 2-week treatment with the non-psychotomimetic cannabinoid cannabidivarin (CBDV) could be beneficial towards neurological and social deficits in early symptomatic Mecp2 mutant mice, a model of Rett syndrome (RTT). Aim: The aim of this study was to provide further insights into the efficacy of CBDV in Mecp2-null mice using a lifelong treatment schedule (from 4 to 9 weeks of age) to evaluate its effect on recognition memory and neurological defects in both early and advanced stages of the phenotype progression. Methods: CBDV 0.2, 2, 20 and 200 mg/kg/day was administered to Mecp2-null mice from 4 to 9 weeks of age. Cognitive and neurological defects were monitored during the whole treatment schedule. Biochemical analyses were carried out in brain lysates from 9-week-old wild-type and knockout mice to evaluate brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1) levels as well as components of the endocannabinoid system. Results: CBDV rescues recognition memory deficits in Mecp2 mutant mice and delays the appearance of neurological defects. At the biochemical level, it normalizes BDNF/IGF1 levels and the defective PI3K/AKT/mTOR pathway in Mecp2 mutant mice at an advanced stage of the disease. Mecp2 deletion upregulates CB1 and CB2 receptor levels in the brain and these changes are restored after CBDV treatment. Conclusions: CBDV administration exerts an enduring rescue of memory deficits in Mecp2 mutant mice, an effect that is associated with the normalization of BDNF, IGF-1 and rpS6 phosphorylation levels as well as CB1 and CB2 receptor expression. CBDV delays neurological defects but this effect is only transient.

All known populations of the Sardinian endemic Centaurea filiformis Viv. (Asteraceae) were studied in order to understand the impact of both geographic and ecological factors on the genetic structuring of this species. Fourteen populations and 234 individuals were sampled. The demographic structure of the populations and the reproductive ecology were estimated in 28 plots. Population genetic analyses were based on SSR markers. Genetic structure was investigated by spatial Bayesian methods. Average densities of 0.51 individuals m-2 were detected, with a prevalence of adults. Ten species of pollinators were identified; C. filiformis ability to self-pollinate and myrmecochory were demonstrated experimentally. The populations displayed an average heterozygosity value of He = 0.576 and high genetic differentiation (overall FST = 0.218). Bayesian analysis suggests that five is the most probable number of gene pools of origin. A strong correlation between geographic distances and genetic distances among populations was highlighted. The demographic population structure of C. filiformis is dominated by adults, suggesting that it is a stable-regressive or senile species, investing more in local persistence than colonisation ability. Despite the scattered distribution, the populations studied do not present evidence of genetic erosion. The analysis of genetic differentiation reveals very high differentiation levels among populations, thus indicating that effective barriers exist against gene flow. A general conclusion is that population distribution results in a clear genetic structure for the populations studied, and that geography and not ecology is shaping the present distribution of this species.

Deregulation of apoptosis is a frequent alteration in early benign lesions of the colon mucosa and is thought to be a major contributor to tumor progression and cancer. Single nucleotide polymorphisms (SNPs) within apoptosis-related genes could affect apoptotic responses and their identification might provide a basis to assess individual risk for development of early lesions. To investigate a possible association between genetic polymorphisms and the occurrence of hyperplastic polyps (HP), we developed a custom DNA chip assay for 1,536 SNPs in the coding and flanking regions of 826 genes with known functional roles in apoptosis or apoptosis-associated (e.g., stress-related) pathways. During a first round of screening, genotypes were determined for 272 endoscopy patients harboring hyperplastic colorectal polyps and for 512 sex and aged-matched controls. A set of 14 candidate SNPs associated with HP (P

International audience; Conifers are key species of many boreal and temperate forests, providing crucial resources to human activities. Adaptation to local climate and long life span make tree species highly susceptible to both short- and long-term environmental changes. Thus, a substantial effect of ongoing climate change on forest viability and production potential is expected. A deeper understanding of the genetic mechanisms that control the adaptive ability of forests can be used for management strategies to assist forests through climate change. Indeed, a reliable and systematic genetic assessment of Norway spruce provenances for their response to extreme climatic conditions could be a prerequisite for a successful assisted migration of this species in a changing environment. The purpose of this study is to investigate, by mean of Single Nucleotide Polymorphisms (SNPs), the genetic bases of local adaptation along altitudinal gradients in 18 natural Alpine populations of Norway spruce (Picea abies [L.] Karst), sampled on a regional scale in Trentino-South Tyrol (Eastern Italian Alps). To account for patterns of gene flow and spatial genetic structure due to alpine landscape features, sampled stands were subdivided into three geographical groups, each including at least one sampled altitudinal gradient. As expected, hierarchical analyses of molecular variance revealed that most of the genetic variability was found within stands, though a little but significant variation was found among geographical groups. To detect potentially adaptive markers, two distinct approaches were used. First, classical outlier loci detection was applied along the altitudinal gradients using both a Bayesian analysis and a Hierarchical Island Model (HIM), which showed contrasting results. Subsequently, Moran’s Eigenvector Maps (MEM) variables, which may account for spatial variation and un-accounted environmental factors, were applied to an allele distribution model, and 19 loci significantly associated to environmental variation were identified. Four of these loci were also detected as outliers by the HIM. The combined approach of selection scan and spatial analysis method allowed for a parallel investigation of Norway spruce adaptive potential in alpine stands, providing evidence for selective forces acting on adaptive loci that could be relevant in forest management.

Background Chronic rhinosinusitis (CRS) is a frequent disease with high social impact and multifactorial pathogenesis. Recently, single nucleotide polymorphisms within the TAS2R38 gene have been implicated as possible contributors to the complex gene-environment interactions in CRS. The purpose of this study was to confirm the proposed correlation between TAS2R38 genotype, CRS and related comorbidities. Methods Fifty-three CRS patients and 39 healthy individuals were genotyped at the TAS2R38 locus. CRS patients were treated by endoscopic sinus surgery and medical therapies and subdivided in CRS with nasal polyps (CRSwNPs) and CRS without nasal polyps (CRSsNPs). The effect of genotype on CRS and CRS-related comorbidities was assessed. Results The distribution of the different genotypes at the TAS2R38 locus was not significantly different between CRS patients, either with or without nasal polyps, and controls. Besides, no association was found between the different genotypes at the TAS2R38 locus and CRS-related comorbidities. Conclusions No association was found between TAS2R38 alleles or genotypes and CRS, thus questioning its role in the pathogenesis of CRS. Electronic supplementary material The online version of this article (doi:10.1186/s12881-016-0321-3) contains supplementary material, which is available to authorized users.

The Antarctic Peninsula has experienced a strong climate warming trend of + 0.53 °C (mean annual air temperature) over the last 50 years. In the Polar Regions, changes in vegetation and permafrost due to a warming climate are expected to produce strong feedbacks to climate and, despite their relatively small areal extent, ice-free areas in Antarctica provide unique natural environments for studying these effects. Off the Antarctic Peninsula, close to Rothera Research Station on Adelaide Island, we used in situ measurements to assess whether spatial variation of CO2 fluxes exists a) among three important and typical vegetation types at Rothera Point during the daylight period; b) across four different ecosystem types (from Antarctic vascular tundra to barren soil) on neighbouring Anchorage Island during the peak of the growing season (January–February 2009). We aimed to assess whether Net Ecosystem Exchange (NEE), Ecosystem Respiration (ER) and Gross Ecosystem Photosynthesis (GEP) change among the selected ecosystem types and determine which environmental factors (soil moisture, soil temperature and PAR) influence NEE and ER. The data obtained at Rothera Point confirmed the presence of spatial variation of CO2 fluxes related to vegetation type, and temporal variation of the CO2 cycle during the daylight period for moss and barren soil ecosystems. At Anchorage Island the spatial variation of CO2 fluxes was mainly influenced by vegetation type at inter-community level. Deschampsia and Sanionia showed higher NEE and ER values (− 0.03 / 0.43 μmol CO2 m− 2 s− 1 for Deschampsia NEE; 0 / 0.62 μmol CO2 m− 2 s− 1 Sanionia NEE; 0.27 / 2.03 μmol CO2 m− 2 s− 1 Deschampsia ER; 0.31 / 1.7 μmol CO2 m− 2 s− 1 Sanionia ER) than the other vegetation types studied. We measured generally positive NEE values probably due to high soil respiration. Our data suggest that ecosystems such as those studied may act as a source for CO2 release to the atmosphere and that this source effect is likely to continue and/or to increase until the “legacy” of organic matter and nutrients stored in the soils is largely decomposed.

The Lesser Flamingo Phoeniconaias minor is a nomadic species, which inhabits shallow alkaline lakes and pans in sub-Saharan Africa and southern Asia. The extent of genetic diversity and the degree of differentiation within and among populations are important factors to determine in order to help manage and conserve the species, categorised as Near Threatened by the IUCN. This study provides an assessment of the population structure of the two largest African populations of P. minor by genotyping six microsatellite loci from 30 individuals sampled on Lake Bogoria (Kenya) and 11 individuals from Makgadikgadi Sua Pan (Botswana). The alleles detected per locus ranged from four to 13. The Lake Bogoria population harboured 15 specific alleles, whereas the Makgadikgadi Sua Pan population only six alleles. Moderate genetic diversity (He = 0.64–0.69) was comparable with populations that have not suffered from demographic bottlenecks or inbreeding. The populations are genetically similar with little differentiation...

How Quaternary climatic and geological disturbances influenced the composition of Neotropical forests is hotly debated. Rain fall and temperature changes during and/or immediately after the Last Glacial Maximum (LGM) are thought to have strongly affected the geographical distribution and local abundance of tree species. The paucity of the fossil records in Neotropical forests prevents a direct reconstruction of such processes. To describe community-level historical trends in forest composition, we turned therefore to inferential methods based on the reconstruction of past demographic changes. In particular, we modelled the history of rainforests in the Eastern Guiana Shield over a time scale of several thousand generations, through the application of Approximate Bayesian Computation (ABC) and Maximum Likelihood (ML) methods to diversity data at nuclear and chloroplast loci in eight species or subspecies of rainforest trees. Depending on the species and on the method applied, we detected population contraction, expansion or stability, with a general trend in favour of stability or expansion, with changes presumably having occurred during or after the LGM. These findings suggest that Guiana Shield rain forests have globally persisted, while expanding, through the Quaternary, but that different species have experienced different demographic events, with a trend towards the increase in frequency of light-demanding, disturbance-associated species.

Forest trees dominate many Alpine landscapes that are currently exposed to changing climate. Norway spruce is one of the most important conifer species of the Italian Alps, and natural populations are found across steep environmental gradients with large differences in temperature and moisture availability. This study seeks to determine and quantify patterns of genetic diversity in natural populations toward understanding adaptive responses to changing climate. Across the Italian species range, 24 natural stands were sampled with a major focus on the Eastern Italian Alps. Sampled trees were genotyped for 384 selected single nucleotide polymorphisms (SNPs) from 285 genes. A wide array of potential candidate genes was tested for correlation with climatic parameters. To minimize false-positive association between genotype and climate, population structure was investigated. Pairwise F ST estimates between sampled populations ranged between 0.000 and 0.075, with the highest values involving the two disjoint populations, Valdieri, on the western Italian Alps, and Campolino, the most southern population on the Apennines. Despite considerable genetic admixture among populations, both Bayesian and multivariate approach identified four genetic clusters. Selection scans revealed five F ST outliers, and the environmental association analysis detected ten SNPs associated to one or more climatic variables. Overall, 13 potentially adaptive loci were identified, three of which have been reported in a previous study on the same species conducted on a broader geographical scale. In our study, precipitation, more than temperature, was often associated with genotype; therefore, it appears as the most important environmental variable associated with the high sensitivity of Norway spruce to soil water supply. These findings provide relevant information for understanding and quantifying climate change effects on this species and its ability to genetically adapt.

Aim In order to look for a possible centre of survival for the Norway spruce (Picea abies Karst.) in the south-western Alps, six natural populations of this area were investigated by means of genetic markers in order to assess the degree and the distribution of genetic diversity within the species. Location Western and South-western Alps. Methods Populations were genotyped using seven simple sequence repeat (SSR) markers. Basic population genetics parameters were estimated and the amount of genetic differentiation calculated. Results A large amount of variability was found (0.59

The hexaploid herbaceous species Primula glaucescens Moretti and Primula spectabilis Tratt. (2n = 6x = 66) are two endemics of the Italian Pre-Alps protected by national and international laws. In order to plan conservation strategies for natural populations and to study the influence of the latest glaciation on them we developed a set of microsatellites markers for the endangered Primula species: ten primer pairs allowed analysis of polymorphic disomic loci in P. glaucescens samples and seven of them also amplified polymorphic disomic markers in P. spectabilis.

Numerous studies have demonstrated a link between genetic markers on chromosome 13 and schizophrenia, bipolar affective disorder, and other psychiatric phenotypes. The G72/G30 genes (transcribed in opposite directions) are located on chromosome 13q33, a region demonstrating strong evidence for linkage with various neuropsychiatric disorders. G72/G30 was identified in 2002 as a schizophrenia susceptibility locus; however, subsequent association studies did not reach consensus on single SNPs within the locus. Simultaneously, a new vision for the genetic architecture of psychiatric disorders suggested that schizophrenia was a quantitative trait, therefore ascribable to potentially hundreds of genes and subjected to the vagaries of the environment. The main protein product of G72 gene is named pLG72 or D-amino acid oxidase activator DAOA (153 amino acids) and its function is still debated. Functional analyses, also showing controversial results, indicate that pLG72 contributes to N-methyl-D-aspartate receptor modulation by affecting activity of the flavoprotein D-amino acid oxidase, the enzyme responsible for degrading the neuromodulator D-serine. In this review we, for the first time, summarize findings from molecular genetic linkage and association studies concerning G72 gene, cellular and molecular studies on pLG72, and investigations performed on G72/G30 transgenic mice. This will help elucidate the role of psychosis susceptibility genes, which will have a major impact on our understanding of disease pathophysiology and thus change classification and treatment.

Background Chronic rhinosinusitis (CRS) is a frequent disease with a high social impact and multifactorial pathogenesis. Recently, single nucleotide polymorphisms (SNPs) within the TAS2R38 gene were pointed at as possible contributors to the complex gene-environment interactions in CRS. This hypothesis was supported by in vitro evidence of the protective effect exerted by the functional bitter taste receptor T2R38 on sinonasal mucosa, due to its role in innate immunity. The purpose of this study was to confirm the proposed correlation between TAS2R38 genotype and CRS comorbidities and to assess whether the presence of a particular allele can be considered a prognostic marker.

� Background and Aims Ulmus minor has been severely affected by Dutch elm disease (DED). The introduction into Europe of the exotic Ulmus pumila, highly tolerant to DED, has resulted in it widely replacing native U. minor populations. Morphological and genetic evidence of hybridization has been reported, and thus there is a need for assessment of interspecific gene flow patterns in natural populations. This work therefore aimed at studying pollen gene flow in a remnant U. minor stand surrounded by trees of both species scattered across an agricultural landscape. � Methods All trees from a small natural stand (350 in number) and the surrounding agricultural area within a 5-km radius (89) were genotyped at six microsatellite loci. Trees were morphologically characterized as U. minor, U. pumila or intermediate phenotypes, and morphological identification was compared with Bayesian clustering of genotypes. For paternity analysis, seeds were collected in two consecutive years from 20 and 28 mother trees. Maximum likelihood paternity assignment was used to elucidate intra- and interspecific gene flow patterns. � Key Results Genetic structure analyses indicated the presence of two genetic clusters only partially matching the morphological identification. The paternity analysis results were consistent between the two consecutive years of sampling and showed high pollen immigration rates (� 0� 80) and mean pollination distances (� 3 km), and a skewed distribution of reproductive success. Few intercluster pollinations and putative hybrid individuals were found. � Conclusions Pollen gene flow is not impeded in the fragmented agricultural landscape investigated. High pollen immigration and extensive pollen dispersal distances are probably counteracting the potential loss of genetic variation caused by isolation. Some evidence was also found that U. minor and U. pumila can hybridize when in sympatry. Although hybridization might have beneficial effects on both species, remnant U. minor populations represent a valuable source of genetic diversity that needs to be preserved.

Long-term follow up studies of hepatitis C virus (HCV) infection rarely exceed 20-25 yr. We studied the outcome of HCV infection in 35-yr-old adults infected at birth (1968) through mini transfusions of blood. A retrospective-prospective study was carried out. The cohort included 31 individuals who were given mini blood transfusions (21-30 ml) collected from a donor subsequently revealed to be HCV infected. At enrollment (1998), 18 of 31 (58.1%) recipients had anti-HCV antibody and 16 (88.9%) of them were HCV-RNA positive. All viremic recipients and the infectious donor had the same genotype 1b. Sequence analysis of E1/E2 and NS5b regions, coupled with phylogenetic analysis, indicated that HCV isolates from donor/recipients were linked. Eleven of the 16 viremic recipients gave consent to liver biopsy. Nine had no fibrosis or mild portal fibrosis and 2 had either discrete (Ishak's staging 3) or marked (Ishak's staging 4) fibrosis. During the prospective follow-up period (1998-2003), 2 patients were given therapy, one of whom achieved sustained clinical and virologic response. A second biopsy, performed in 5 patients at a 5 yr interval, revealed no substantial modifications in 4 cases and progression from absence of fibrosis to mild portal fibrosis in the fifth. In conclusion, taking into account the limited study sample, these findings suggest that HCV infection acquired early in life shows a slow progression and mild outcome during the first 35 yr of infection.

During vertebrate evolution, the uric acid degradation pathway has been modified and several enzymes have been lost. Consequently, the end product of purine catabolism varies from species to species. In the past few years, we have focused our attention on vertebrate allantoicase (an uricolytic pathway enzyme), whose activity is present in certain fish and amphibians only, but whose mRNA we detected also in mammals. As allantoicase activity disappeared in amniotes, we wonder why these sequences not only remain present in the mammalian genome, but are still transcribed. To elucidate this issue, we have cloned and analyzed comparable cDNA sequences of different organisms from ascidians to mammals. The analysis of the nonsynonymous-synonymous substitution rate that we performed on the coding region comprising exons 3 to 8 by means of maximum likelihood suggested that a certain amount of purifying selection is acting on the allantoicase sequences. Some implications of the preservation of an apparently unnecessary gene in higher vertebrates are discussed.

We identified 15 patients with acute hepatitis C (AHC) among 29 healthy volunteers participating in 2 consecutive pharmacokinetics studies. Molecular techniques were used to determine the relatedness of viral strains, whereas clinical and virologic follow-up was started to establish the course and outcome of the acute infection. After presentation, serum liver enzymes and HCV RNA were monitored weekly for 4 months, then monthly for at least 12 months. Liver biopsy was performed 6 to 12 months after AHC diagnosis. Phylogenetic analysis of coding regions for the envelope glycoproteins E1 and E2 was performed. At presentation, all 15 patients tested HCV RNA–positive and had HCV genotype 2c. Phylogenetic analysis indicated a common source of infection. Fourteen patients agreed to be followed prospectively. Infection resolved spontaneously in 8 patients, HCV RNA becoming undetectable by 4 to 5 months after the presumed time of infection in 5 of them and by 8, 13, and 24 months in the remaining 3. Six patients developed chronic infection. Liver biopsies performed in 9 subjects who were HCV RNA–positive 6 months after AHC diagnosis revealed that the prevalent histologic finding was lobular inflammation. In conclusion, our homogeneous cohort showed a wide spectrum of clinical, virologic and histologic features, and, more importantly, short-term outcome differed noticeably despite the common source of infection. (H EPATOLOGY 2002;36:993-1000.)

An investigation of the genetic variability of Octopus vulgaris, an intensively harvested species, was carried out using a mi crosatellite locus as genetic marker. Samples from one eastern At lantic and nine Mediterranean locations were analysed. In each population, the number of alleles at locus Ov06 varied from four to seven and was 21 overall. Observed and expected heterozy‐gosity values ranged from 0.310 to 0.655 and 0.506 to 0.841, re spectively. Permutation tests and the positive average value of FIS showed significant departures from the Hardy‐Weinberg equilibri um, due to a deficit of heterozygotes. FST showed high levels of genetic divergence among the populations. Genetic distance val ues ranged from 0.0004 to 7.1520. Isolation‐by‐distance was not evident either by the Mantel test or multidimensional scaling. Mi crosatellite results are consistent with a previous allozyme study, and suggest that the common octopus does not form a single panmictic unit in the Mediterranean. From a fisher...

We performed a case-control study to evaluate the association of a new human DNA virus named TT virus (TTV) with hepatocellular carcinoma (HCC). We recruited 174 subjects hospitalized for HCC (84% males; mean age: 64 years) and 118 patients hospitalized for non-liver diseases in Brescia, northern Italy, as controls (94% males; mean age: 66 years). TTV DNA was found in serum by polymerase chain reaction (PCR) in 26 cases (15%) and 11 controls (9.3%) (P > .1). TTV group 2 infection was identified in 16 cases (61.5%) and 4 controls (36.4%) (P > .1) using a type-specific PCR method. Sequence analysis of 222 nt of TTV DNA demonstrated that the remaining 10 cases and 7 controls were all infected by group 1. The odds ratio (OR) for TTV-DNA positivity, adjusted for demographic variables, hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) RNA, and heavy alcohol intake was 1.8 (95% CI: 0.7-4.8; P > .1). The OR did not change when the analysis was restricted to 14 HCC cases and 56 controls who were negative for each known risk factor for HCC (OR = 1.7; 95% CI: 0.8-4.0). TTV-DNA positivity was not associated with transfusion history. The prevalence of TTV DNA was higher among HCC cases positive for HBsAg (10 of 38 [26.3%]) than among those positive for HCV RNA (8 of 62 [12.9%]) or negative for hepatitis B virus (HBV), HCV, and hepatitis G virus (HGV) infections (5 of 62 [8.1%]) (P = .02). This study does not support the hypothesis of an association between TTV infection and HCC.

Segregation of mutant mtDNA in human tissues and through the germline is debated, with no consensus about the nature and size of the bottleneck hypothesized to explain rapid generational shifts in mutant loads. We investigated two maternal lineages with an apparently different inheritance pattern of the same pathogenic mtDNA 3243A>G/tRNALeu(UUR) (MELAS) mutation. We collected blood cells, muscle biopsies, urinary epithelium and hair follicles from 20 individuals, as well as oocytes and an ovarian biopsy from one female mutation carrier, all belonging to the two maternal lineages to assess mutant mtDNA load, and calculated the theoretical germline bottleneck size (number of segregating units). We also evaluated "mother-to- offspring" segregations from the literature, for which heteroplasmy assessment was available in at least three siblings besides the proband. Our results showed that mutation load was prevalent in skeletal muscle and urinary epithelium, whereas in blood cells there was an inverse correlation with age, as previously reported. The histoenzymatic staining of the ovarian biopsy failed to show any cytochrome-c-oxidase defective oocyte. Analysis of four oocytes and one offspring from the same unaffected mother of the first family showed intermediate heteroplasmic mutant loads (10% to 75%), whereas very skewed loads of mutant mtDNA (0% or 81%) were detected in five offspring of another unaffected mother from the second family. Bottleneck size was 89 segregating units for the first mother and 84 for the second. This was remarkably close to 88, the number of "segregating units" in the "mother-to- offspring" segregations retrieved from literature. In conclusion, a wide range of mutant loads may be found in offspring tissues and oocytes, resulting from a similar theoretical bottleneck size.

Alcolapia is a minor genus of small-bodied, polymorphic cichlids inhabiting the lagoons and hot springs surrounding the soda lakes Natron (largely in Tanzania) and Magadi (Kenya). Three Alcolapia species are present at Natron (Alcolapia alcalicus, Alcolapia ndalalani and Alcolapia latilabris) and one at Magadi (Alcolapia grahami). All are IUCN Red Listed as either vulnerable or endangered. We performed analyses of morphometric and genetic structure on 13 populations of the Natron Alcolapia flock, and one A. grahami population of Lake Magadi as an out-group. Morphometric analyses revealed significant differentiation in the head and mouth shape of the species at Natron. From a genetic perspective, among 70 mtDNA control region sequences 17 haplotypes were found, showing in the minimum spanning network a star-like pattern around the widespread haplotype 2lat. At Natron, there was limited genetic differentiation between the different populations of A. alcalicus and A. latilabris, despite apparent ecological barriers of extreme alkalinity that suggested their populations were isolated. Instead, there appeared to be some population connectivity, with a rate of 0.5–2.3 migrants per generation suggesting that natural factors, such as intense rains or transmission by large piscivorous birds, facilitate population connectivity and maintain genetic similarity. The outputs of high population connectivity and one genetic unit at the basin level (despite morphological divergence) suggest that any human activities that disrupt the connectivity of the freshwater resources of the Natron catchment could further threaten the integrity and current status of these already threatened fish populations.

Deregulation of apoptosis is a frequent alteration in early benign lesions of the colon mucosa and is thought to be a major contributor to tumor progression and cancer. Single nucleotide polymorphisms (SNPs) within apoptosis-related genes could affect apoptotic responses and their identification might provide a basis to assess individual risk for development of early lesions. To investigate a possible association between genetic polymorphisms and the occurrence of hyperplastic polyps (HP), we developed a custom DNA chip assay for 1,536 SNPs in the coding and flanking regions of 826 genes with known functional roles in apoptosis or apoptosis-associated (e.g., stress-related) pathways. During a first round of screening, genotypes were determined for 272 endoscopy patients harboring hyperplastic colorectal polyps and for 512 sex and aged-matched controls. A set of 14 candidate SNPs associated with HP (P 0.01) was then evaluated in an independent cohort of patients (n = 38) and controls (n = 38). Following meta-analysis of Stages I and II, a false discovery rate approach was applied. Among the 14 candidate SNPs, eight showed significant association (combined P 0.01) with the occurrence of HP. The SNPs rs4709583 (PARK2) and rs10476823 (HDAC3) were analyzed for potential functional effects on RNA splicing and RNA half-life. Despite its location near a splice site, alternative splicing was not detected for rs4709583 (PARK3). By contrast, cDNA analysis revealed use of a cryptic polyadenylation signal in the 3'UTR of HDAC3 mRNA and a longer mRNA half-life in a cell line heterozygous for rs10476823.

In order to detect the genetic architecture of maize tolerance to Alachlor, a widely used chloroacetanilide, linkage analysis between the expression of the trait and allelic composition of molecular markers was performed. The experiment was carried out on a population of 142 recombinant inbred lines, developed starting from the F1 between two lines with different reactivity to the herbicide, and self-fertilized for 10 generations; the lines were typed by 48 RFLP markers and 66 microsatellites (SSR). Besides seedling tolerance, evaluated as proportion of normal (non-injured) plants after herbicide treatment, other minor components of tolerance were studied: seed germination ability, pollen germination and tube growth in the presence of the herbicide. The analysis, performed by three statistical methods, revealed the presence of factors controlling seedling tolerance on seven chromosomal regions. Five QTLs appeared to be involved in seed germination ability in the presence of Alachlor, four QTLs in pollen tolerance in terms of germination and four in tube growth under stress were detected. Three loci, on chromosomes 1, 7 and 10, explained most of the variation of seedling tolerance, thus being interesting candidate for marker-assisted selection.

Abstract Previous studies on genetic rat hypertension have shown that polymorphism within the α-adducin gene may regulate blood pressure. Adducin is a cytoskeletal protein that may be involved in cellular signal transduction and interacts with other membrane-skeleton proteins that affect ion transport across the cell membrane. There is a high homology between rat and human adducin and pathophysiological similarities between the Milan hypertensive rat strain and a subgroup of patients with essential hypertension. Thus, we designed a case-control study to test the possible association between the α-adducin locus and hypertension. One hundred ninety primary hypertensive patients were compared with 126 control subjects. All subjects were white and unrelated. Four multiallelic markers surrounding the α-adducin locus located in 4p16.3 were selected: D4S125 and D4S95 mapping at 680 and 20 kb centromeric, and D4S43 and D4S228/E24 mapping at 660 and 2500 kb telomeric. Alleles for each marker were pooled into groups. Comparisons between control subjects and hypertensive patients were carried out by testing the allele-disease association relative to the marker genotype. The maximal association occurred for D4S95 (χ 1 2 13.33), which maps closest to α-adducin. These data suggest that a polymorphism within the α-adducin gene may affect blood pressure in humans.

In order to detect loci specifically related to pollen–style interaction in maize, linkage analysis to RFLP markers was performed on a population of recombinant inbred lines, the pollen of which was used to pollinate female plants of two different genotypes: the F1 from which the recombinant inbred population was derived (‘self female’) and a genetically unrelated hybrid genotype (‘cross female’). Besides pollen grain germinability and pollen tube growth rate on the two females, pollen general competitive ability and pollen specific competitive ability for both traits were evaluated, following the procedure used to estimate general and specific combining ability, applied to the pollen-style genetic combination instead of to the hybrid genetic combination. A clear advantage of recombinant inbred line pollen, in terms of germination and early growth, was revealed on self female tissues whereas an inverse effect was detected for tube growth rate: tube growth, until fertilization, was faster on the female of unrelated genotype. Linkage analysis to molecular markers (RFLP) of germinability and of tube growth rate on the two stylar genotypes identified nine QTLs for the first trait on the self and eight on the cross female; four chromosome regions for tube growth rate were detected on the self and 11 on the cross style. Most of the general competitive ability effects were localized in the regions where QTLs for germinability or pollen tube growth were detected, in particular on the cross female; on the contrary, most of the loci for pollen specific competitive ability effects proved to be localized in different chromosome regions.

The C3H/He mouse represents a good experimental model of genetic predisposition to hepatocellular tumor development. We analyzed an interspecific test-cross population of 106 urethane-treated male (C3H/He x Mus spretus) x C57BL/6J mice, typed with 222 genetic markers to locate precisely the hepatocellular tumor susceptibility (Hcs) loci. Three regions, on chromosomes 2, 5, and 19, showed a significant linkage with hepatocellular tumor development, as indicated by different quantitative indexes estimating liver tumor size. Liver tumor frequency was not genetically controlled. These loci are different from three other Hcs loci that we have previously mapped in an F2 progeny of the C3H/He mouse crossed with the resistant laboratory strain A/J. The present result indicates a multigenic model of inheritance for hepatocellular tumor susceptibility.

Norway spruce (Picea abies Karst.) is a most important species among European forest trees for both economical and ecological reasons. However, this species has suffered from a lack of information on the genetic side due to the scarcity of linkage data. In this study we have used a population of 72 megagametophytes from a single tree in a natural Italian stand to produce a genetic linkage map by means of RAPD markers. Ninety-six random decamers used as primers yielded 185 polymorphic loci showing Mendelian inheritance. Analysis of the segregation by multipoint analysis allowed us to define 17 major linkage groups covering a total distance of 3584 cM, with an average spacing between markers of 22 cM. Possible uses of a genetic linkage map with respect to population ecology and genetics are discussed.

Lung tumours represent a major cause of death in humans, and although smoking represents the main pathogenetic factor, inheritance also plays a part. However, the identification of possible predisposing genetic factors is difficult, because of their low penetrance. We took advantage of murine strains that are genetically susceptible or resistant to lung tumour development, to map murine genes associated with susceptibility to lung carcinogenesis. An F2 population of urethan-treated A/J x C3H/He mice was scored with 83 genetic markers. A chromosome 6 distal region, spanning mice was scored with 83 genetic markers. A chromosome 6 distal region, spanning 35 centiMorgans, contained a major lung tumour susceptibility locus. No other chromosomal region was significantly associated with lung tumour development.

Clinical and laboratory studies suggest that the endocannabinoid system is involved in schizophrenia disorders. Recent evidence indicates that cannabinoid receptor (CB1) antagonists have a pharmacological profile similar to antipsychotic drugs. We investigated the behavioural and biochemical effects of the CB1 antagonist AM251 in a phencyclidine (PCP) animal paradigm modelling the cognitive deficit and some negative symptoms of schizophrenia. Chronic AM251 (0.5 mg/kg for 3 wk) improved the PCP-altered recognition memory, as indicated by a significant amelioration of the discrimination index compared to chronic PCP alone (2.58 mg/kg for 1 month). AM251 also reversed the PCP-induced increase in immobility in the forced swim test resembling avolition, a negative sign of schizophrenia. In order to analyse the mechanisms underlying these behaviours, we studied the effects of AM251 on the endocannabinoid system (in terms of CB1 receptor density and functional activity and endocannabinoid levels) and c-Fos protein expression. The antagonist counteracted the alterations in CB1 receptor function induced by PCP in selected cerebral regions involved in schizophrenia. In addition, in the prefrontal cortex, the key region in the integration of cognitive and negative functions, AM251 markedly raised anandamide levels and reversed the PCP-induced increase of 2-arachidonoylglycerol concentrations. Finally, chronic AM251 fully reversed the PCP-elicited expression of c-Fos protein in the prefrontal cortical region. These findings suggest an antipsychotic-like profile of the CB1 cannabinoid receptor antagonist which, by restoring the function of the endocannabinoid system, might directly or indirectly normalize some of the neurochemical maladaptations present in this schizophrenia-like animal model.

Studies over the last two decades demonstrate that hybridization has played an integral role in the evolution of several sections of the genus Centaurea. Nevertheless, natural hybridization between narrow Mediterranean endemic Centaurea species has not been documented as yet. A population of fertile Centaurea individuals exhibiting intermediate morphological traits between two Sardinian narrow endemics, C. horrida and C. filiformis, was identified at the Tavolara Islet (Sardinia, Italy). Intermediate leaf length and head width characterized this population, suggesting its hybrid origin. The putative hybrid population was structured (i.e., composed of seedlings, saplings and adult individuals) and had a relatively high levels of seed production. The number of chromosomes was identical to that of the proposed progenitors (2n = 18). Genotyping at five microsatellite loci showed that the putative hybrid possessed several alleles in common with the proposed parental species and intermediate values of genetic differentiation, as indicated by both FST and RST, between C. horrida and C. filiformis. We therefore conclude that the studied intermediate population is of hybrid origin, and discuss possible mechanisms of its reproductive isolation from the parental species, potential re-introgression, and evolutionary implications of this hybridization.