Characterization of black spot resistance in diploid roses with QTL detection, meta-analysis and candidate-gene identification.

KEY MESSAGE: Two environmentally stable QTLs linked to black spot disease resistance in the Rosa wichurana genetic background were detected, in different connected populations, on linkage groups 3 and 5. Co-localization between R-genes and defense response genes was revealed via meta-analysis. The widespread rose black spot disease (BSD) caused by the hemibiotrophic fungus Diplocarpon rosae Wolf. is efficiently controlled with fungicides. However, in the actual context of reducing agrochemical use, the demand for rose bushes with higher levels of resistance has increased. Qualitative resistance conferred by major genes (Rdr genes) has been widely studied but quantitative resistance to BSD requires further investigation. In this study, segregating populations connected through the BSD resistant Rosa wichurana male parent were phenotyped for disease resistance over several years and locations. A pseudo-testcross approach was used, resulting in six parental maps across three populations. A total of 45 individual QTLs with significant effect on BSD resistance were mapped on the male maps (on linkage groups (LG) B3, B4, B5 and B6), and 12 on the female maps (on LG A1, A2, A3, A4 and A5). Two major regions linked to BSD resistance were identified on LG B3 and B5 of the male maps and were integrated into a consensus map built from all three of the male maps. A meta-analysis was used to narrow down the confidence intervals of individual QTLs from three populations by generating meta-QTLs. Two 'hot spots' or meta-QTLs were found per LG, enabling reduction of the confidence interval to 10.42 cM for B3 and 11.47 cM for B5. An expert annotation of NBS-LRR encoding genes of the genome assembly of Hibrand et al. was performed and used to explore potential co-localization with R-genes. Co-localization with defense response genes was also investigated.

The eyespot resistance genes Pch1 and Pch2 of wheat are not homoeoloci.

KEY MESSAGE: Phenotyping and mapping data reveal that chromosome intervals containing eyespot resistance genes Pch1 and Pch2 on 7D and 7A, respectively, do not overlap, and thus, these genes are not homoeloci. Eyespot is a stem-base fungal disease of cereals growing in temperate regions. Two main resistances are currently available for use in wheat. Pch1 is a potent single major gene transferred to wheat from Aegilops ventricosa and located on the distal end of chromosome 7D. Pch2, a moderate resistance deriving from Cappelle Desprez, is located at the end of 7AL. The relative positions of Pch1 and Pch2 on 7D and 7A, respectively, suggest that they are homoeoloci. A single seed decent recombinant F7 population was used to refine the position of Pch2 on 7A. New markers designed to 7D also allowed the position of Pch1 to be further defined. We exploited the syntenic relationship between Brachypodium distachyon and wheat to develop 7A and 7D specific KASP markers tagging inter-varietal and interspecific SNPs and allow the comparison of the relative positions of Pch1 and Pch2 on 7D and 7A. Together, phenotyping and mapping data reveal that the intervals containing Pch1 and Pch2 do not overlap, and thus, they cannot be considered homoeloci. Using this information, we analysed two durum wheat lines carrying Pch1 on 7A to determine whether the Ae.ventricosa introgression extended into the region associated with Pch2. This identified that the introgression is distal to Pch2 on 7A, providing further evidence that the genes are not homoeoloci. However, it is feasible to use this material to pyramid Pch1 and Pch2 on 7A in a tetraploid background and also to increase the copy number of Pch1 in combination with Pch2 in a hexaploid background.

Durable resistance to stripe rust is due to three specific resistance genes in French bread wheat cultivar Apache.

Quantitative resistance is postulated to be more durable than qualitative (R-gene mediated) resistance, which is usually quickly overcome by the pathogen population. Despite its wide use for nearly 10 years in France, the French bread wheat cultivar Apache remains resistant to stripe rust. Here, we investigated the genetic architecture of cv. Apache resistance to examine whether its durability could be explained by quantitative characteristics. We identified quantitative trait loci (QTL) by composite interval mapping of disease progress data recorded throughout 4 years of field assays. These assays included inoculation with three different pathotypes on a segregating population originating from a cross between cv. Apache and cv. Taldor, a French cultivar susceptible to stripe rust. Three QTLs derived from Apache, QYr.inra-2AS, QYr.inra-2BL and QYr.inra-4B, were detected. Each of these QTLs contributed between approximately 15 and 69 % of the phenotypic variance and corresponds to a race-specific resistance gene. We showed that QYr.inra-2AS and QYr.inra-2BS map to the positions of Yr17 and Yr7, respectively, whereas QYr.inra-4B corresponds to an adult plant resistance gene. Our results demonstrate that a combination of two or more race-specific resistance genes can confer durable resistance provided that it is properly managed at a continental level. Race-specific resistance genes should not be removed from breeding programs provided that they are properly managed.

[What was new in ambulatory general internal medicine in 2011?]. / Nouveautés 2011 en médecine interne générale ambulatoire.

This review of articles published in 2011 covers a large spectrum of topics that are of interest for the practice of general internal medicine and of primary care. Authors discuss public health issues, such as sleep disorders and their relationship with subsequent weight disorders, and the benefits of commercial weight reduction programs. Clinical topics, such as the management of victims of sexual violence and screening strategies for lung cancer, streptococcal pharyngitis, functional bowel disorders and hypertension in ambulatory settings are also reviewed. Besides, authors cover therapeutic issues, such as the treatment of hand arthritis with chondroitin sulfate and the management of plantar warts with salicylic acids and cryotherapy.

First Report of Pseudomonas syringae pv. actinidiae, the Causal Agent of Bacterial Canker of Kiwifruit in France.

In June 2010, young plants of kiwifruit growing in the French regions of Rhone-Alpes (Actinidia deliciosa 'Summer') and Aquitaine (A. chinensis 'Jintao') showed small, angular, necrotic leaf spots and cankers on some canes that was sometimes associated with production of a red exudate. Most of the affected canes died, and in a few cases after a few months, the entire plant died. Symptoms were consistent with Pseudomonas syringae pv. actinidiae, a bacterium that affects several species of Actinidia (A. deliciosa and A. chinensis, the two most important commercial species of kiwifruit). A recent outbreak of this disease is devastating the Italian kiwifruit industry. Bacterial colonies were isolated on King's medium B (KB) from leaf spots and infected canes. Three isolates from Aquitaine and 10 from Rhone-Alpes were retained for further characterization. The 13 isolates were gram negative, induced a hypersensitive reaction when infiltrated in tobacco plants, did not have a cytochrome c oxidase, an arginine dehydrolase or urease activity, did not hydrolyze esculin, starch, or gelatine, and did not induce ice nucleation. When plated on KB, these strains did not show strong fluorescence usually associated with strains of P. syringae. Complete lack of fluorescence reported for the pathotype strain ICMP 9817 has not been observed for those strains. They showed the same weak fluorescence as the strains of P. syringae pv. actinidiae recently isolated from Italy. Those characteristics match those of strains of P. syringae pv. actinidiae (3). Using total DNA of the 13 strains, the pathotype strain, and primers PsaF1/R2 (2), a 280-bp fragment was amplified by PCR, supporting the strains as being P. syringae pv. actinidiae. The amplicon from 6 of the 13 strains was sequenced and found to be 100% similar to the corresponding DNA fragment of the pathotype strain ICMP 9617 (GenBank AY342165). Partial sequences of 1,381 bp of the 16S rDNA gene of four of the six isolates, three strains isolated from Rhone-Alpes and one strain isolated from Aquitaine, were obtained by amplification with primers 27f and 1492r (1). Except for the sequence of strain 181, which was isolated from Aquitaine and had a 1 bp difference (GenBank JF323026), the other sequences were 100% identical to each other (GenBank JF323027 to JF323029). These four sequences were 99% identical to the 16SrDNA sequences of ICMP 9617, the pathotype strain of P. syringae pv. actinidiae (GenBank AB001431). These four strains and the pathotype strain were sprayed (1 × 109 CFU/ml) on leaves of four 6- to 8-week-old seedlings of A. chinensis each. After 4 days, small, necrotic, angular spots were found on all plants inoculated with those four strains and the pathotype strain. No symptoms were found on plants treated with water only. From those leaf spots, bacteria that had all the characteristics of P. syringae pv. actinidiae (as previously described) were isolated. Recently, two different haplotypes for the housekeeping gene cts were described for P. syringae pv. actinidiae (4), the strains isolated from France belong to the haplotype I. This is the same haplotype to which strains isolated from the recent Italian outbreak also belong. To our knowledge, this is the first report of bacterial canker of kiwifruit in France. References: (1) V. Gurtler and V. A. Stanisich. Microbiology 142:3 1996. (2) J. Rees-George et al. Plant Pathol. 59:453, 2010. (3) Y. Takikawa et al. Ann. Phytopathol. Soc. Jpn. 55:437, 1989. (4) J. L. Vanneste et al. N.Z. Plant Prot. 63:7, 2010.

[Sex workers: limited access to healthcare]. / Travailleuses du sexe: un accès aux soins limité?

Sex workers constitute a heterogeneous group possessing a combination of vulnerability factors such as geographical instability, forced migration, substance addiction and lack of legal residence permit. Access to healthcare for sex workers depends on the laws governing the sex market and on migration policies in force in the host country. In this article, we review different European health strategies established for sex workers, and present preliminary results of a pilot study conducted among 50 sex workers working on the streets in Lausanne. The results are worrying: 56% have no health insurance, 96% are migrants and 66% hold no legal residence permit. These data should motivate public health departments towards improving access to healthcare for this vulnerable population.

[Validation of clinical scores: theoretical and practical basic notions]. / Validation des SCORES cliniques: notions théoriques et pratiques de base.

Physicians are using clinical scores on a regular basis. These scores are generally helpful in making medical decisions. However, the process of validation of clinical scores is often unknown to the physicians. This paper reviews the theory of validation of clinical scores and proposes practical exercises.

Characterization of genetic components involved in durable resistance to stripe rust in the bread wheat 'Renan'.

Stripe rust, caused by Puccinia striiformis f. tritici, is one of the most widespread and destructive wheat diseases in areas where cool temperatures prevail. The wheat cv. Renan, carrying the specific gene Yr17, has shown effective resistance for a long time, even though some pathotypes overcame the Yr17 gene. The objectives of this study were to locate and map genetic loci associated with adult-plant resistance (APR) to stripe rust in a recombinant inbred line population derived from a cross between Renan (resistant) and Récital (susceptible). Field assays were performed for 4 years (1995, 1996, 2005, and 2006) to score disease-progress data and identify APR quantitative trait loci (QTLs). Three QTLs, QYr.inra-2BS, QYr.inra-3BS, and QYr.inra-6B, with resistance alleles derived from Renan were detected in 1995 to 1996 with the 237E141 pathotype, which is avirulent against genotypes carrying Yr17. These QTLs were stable and explained a major part of the phenotypic variation seen in 2005 to 2006, when the 237E141 V17 pathotype was used. Each of these QTLs contributed approximately 4 to 15% of the phenotypic variance and was effective at different adult plant stages. Interactions were observed between some markers of the Yr17 gene and three Renan QTLs: QYr.inra-2BS, QYr.inra-3BS, and QYr.inra-6B. Resistance based on the combination of different APR types should provide durable resistance to P. striiformis.

[Health care for migrant patients: primary care or specialized medicine?]. / Patients migrants au cabinet médical: médecine générale ou pratique spécialisée?

When consulting with migrant patients, general practitioners should pay special attention to the quality of their communication, because language barriers and cultural differences may arise. They must also be aware that life events experienced in the home country, during transit and in the host country can impact negatively on their patients' health, and thus a detailed history must be carefully obtained. Finally, they must be conscious that the migratory policies of the host country can influence the delivery of health care to migrant patients as well as their health status.

[Cultural diversity and stereotyping: implication for the medical practice]. / Diversité culturelle et stéréotypes: la pratique médicate est aussi concernée.

Increasing number of migrants worldwide brings doctors to treat patients of various origins. Patients' diversity enriches health professionals but also induces a risk of mutual incomprehension, due to cultural and language barriers. Multicultural context stimulates unwittingly stereotyping, based on a simplistic assessment of the patient's culture. Stereotyping is also influenced by the political and media coverage. Studies underscored that universally, minorities patients have an unequal access to health care in host countries. Health professionals should be aware that racial stereotyping exists in medical practice: it is a first step to bridge cultural gap between them and their patients.

Influence of fibroblast growth factor on phosphorylation and activity of a 34 kDa lipocortin-like protein in bovine epithelial lens cells.

We examined the effect of basic fibroblast growth factor (FGF) on phosphorylation and lipocortin-like activity of the 34 kDa protein present in the basal membrane of epithelial peripheral cells which initiate growth and differentiation in the bovine lens. We found that: (i) the 34 kDa protein possesses anti-phospholipase A2 (PLA2) activity of lipocortin; (ii) in response to FGF, the anti-PLA2 activity of this protein is enhanced whereas its phosphorylation is markedly decreased. It is suggested that the 34 kDa protein might represent an important biological activity in controlling FGF induction of growth and differentiation in the adult eye lens.

Site-specific proteolytic cleavage of Ku protein bound to DNA.

Ku protein, a relatively abundant nuclear protein associated with DNA of mammalian cells, is known to be a heterodimer with subunits of 85 and 72 kDa which binds in vitro to DNA ends and subsequently translocates along the molecule. The functional role played by this protein in the cell, however, remains to be elucidated. We have observed here that Ku protein, purified from cultured monkey cells, is the target of specific endoproteolysis in vitro, by which the 85 kDa subunit is cleaved at a precise site while the 72 kDa subunit remains intact. This cleavage releases an 18 kDa polypeptide and converts Ku protein into a heterodimer composed of the 72 kDa subunit associated with a 69 kDa fragment from the 85 kDa subunit. The proteolyzed form of Ku protein, denoted Ku', has DNA binding properties similar to those of Ku protein. The proteolytic mechanism, which is inhibited by leupeptin and chymostatin, is extremely sensitive to ionic conditions, in particular to pH, being very active at pH 7.0 and completely inhibited at pH 8.0. In addition, cleavage occurs only when Ku protein is bound to DNA, not free in solution. We suggest that in vivo, such proteolysis might be necessary for Ku protein function at some stage of the cell cycle.

Measles in a west African nomadic community.

A serological survey was conducted among Tuareg nomads to determine their level of immunity to measles. More than half (57.9%) of the children under 10 years of age did not have detectable antibodies to measles, suggesting that transmission of the disease is low in this mobile population. Mothers' reports of their children's history of measles were accurate (positive predictive value 93.9% for under-5-year-olds). Nomads are a reservoir of susceptible individuals who require immunization strategies adapted to their particular life-styles. These can be implemented at relatively low cost.

Analysis of the mechanism of interaction of simian Ku protein with DNA.

Ku protein is a relatively abundant DNA-binding protein which was first detected as the autoantigen in a patient with scleroderma-polymyositis overlap syndrome (hence the name 'Ku'). It is a heterodimer of two polypeptide chains of molecular weights 85,000 and 72,000, and it characteristically binds, in vitro, to the ends of DNA fragments, and translocates to form regular multimeric complexes, with one protein bound per 30 bp of DNA. We have studied the mechanism of interaction of Ku protein with DNA in vitro, using protein extracted from cultured monkey cells. We find that the precise structure of the DNA ends is not important for binding, as Ku protein can bind to hairpin loops and to mononucleosomes. Bound protein also does not require DNA ends for continued binding, since complexes formed with linear DNAs can be circularized by DNA ligase. Dissociation of the complex also appears to require DNA ends, since ligase closed circular complexes were found to be extremely stable even in the presence of 2 M NaCl. We also found that Ku molecules slide along DNA, with no preferential binding to specific sequences. Thus, Ku protein behaves like a bead threaded on a DNA string, a binding mechanism which allows us to make a new hypothesis concerning the function of this protein in the nucleus.

[A migrating ear of barley: a curious story of an intrabronchial foreign body]. / L'épi d'orge migrateur: une curieuse histoire de corps étranger intrabronchique.

A case of migrating inhaled ear of barley in a 2 1/2 year old boy is reported with: 1) mild initial symptoms at the time of inhalation followed by a symptomless interval of 8 days; 2) at day 9 fever and dyspnea, right paracardiac infiltrate with pleural reaction on X-rays, normal bronchoscopy; 3) at day 11 extensive right pneumothorax; 4) at day 20, right axillary inflammatory lesion; 5) at day 28 expulsion of an ear of barley from this lesion, followed by complete recovery.

Phosphorylation and lipocortin-like activity of a 34-kD surface protein in lens epithelial cells: relation to mitogenesis induced by basic fibroblast growth factor.

In order to elucidate the molecular mechanism whereby basic fibroblast growth factor (bFGF) exerts its action on cell proliferation, we investigated the possible relationship between the mitogenic response to bFGF of bovine lens epithelial cells and the phosphorylation and phospholipase A2 (PLA2) activity of a 34-kD protein (p34) present in the basal plasma membrane of these cells. When p34 was obtained from the peripheral epithelial cells which were not capable of being stimulated with bFGF, pretreatment with bFGF led to decreased phosphorylation and PLA2 activity of p34. In contrast, both an increased phosphorylation of p34 and a strong activation of PLA2 occurred when p34 was derived from the central epithelium which was induced to proliferate in the presence of bFGF. It is hypothesized that p34 might play a key role as part of signal transduction of bFGF in controlling DNA synthesis of bovine lens epithelial cells.

Detection of QTLs for Stagonospora glume blotch resistance in Swiss winter wheat.

Stagonospora nodorum is the causal agent of the Stagonospora glume blotch disease in hexaploid wheat. The Swiss winter bread wheat cv. 'Arina' has a highly effective, durable and quantitative glume blotch resistance. We studied 240 single seed descent (SSD)-derived lines of an 'Arina x Forno' F(5:7) population to identify and map quantitative trait loci (QTLs) for glume blotch resistance under natural infestation. Using composite interval mapping (CIM) and LOD>4.5, we detected two chromosomal regions on chromosome arms 3BS and 4BL which were specifically associated with glume blotch resistance. These identified QTLs were designated QSng.sfr-3BS and QSng.sfr-4BL, respectively. QSng.sfr-3BS peaked at the locus Xgwm389 in the telomeric region of the short arm of chromosome 3B and explained 31.2% of the observed phenotypic variance for the resistance within the population. The responsible QSng.sfr-3BS allele originated from the resistant parent 'Arina'. The QTL QSng.sfr-4BL (19.1%) mapped to chromosome arm 4BL ('Forno' allele) very close to two known genes, TaMlo and a catalase ( Cat). Both QTL alleles combined could enhance the resistance level by about 50%. Additionally, they showed significant epistatic effects (4.4%). We found PCR-based microsatellite markers closely linked to QSng.sfr-3BS (gwm389) and QSng.sfr-4BL (gwm251) which make marker-assisted selection (MAS) for Stagonospora glume blotch resistance feasible. We also found one resistance QTL, QSng.sfr-5BL, on the long arm of chromosome 5B which overlapped with QTLs for plant height as well as heading time.

Dissection of quantitative and durable leaf rust resistance in Swiss winter wheat reveals a major resistance QTL in the Lr34 chromosomal region.

The Swiss winter bread wheat cv. 'Forno' has a highly effective, durable and quantitative leaf rust ( Puccinia triticina Eriks.) resistance which is associated with leaf tip necrosis (LTN). We studied 240 single seed descent lines of an 'ArinaxForno' F(5:7 )population to identify and map quantitative trait loci (QTLs) for leaf rust resistance and LTN. Percentage of infected leaf area (%) and the response to infection (RI) were evaluated in seven field trials and were transformed to the area under the disease progress curves (AUDPC). Using composite interval mapping and LOD >4.4, we identified eight chromosomal regions specifically associated with resistance. The largest and most consistent leaf rust resistance locus was identified on the short arm of chromosome 7D (32.6% of variance explained for AUDPC_% and 42.6% for AUDPC_RI) together with the major QTL for LTN ( R(2)=55.6%) in the same chromosomal region as Lr34 ( Xgwm295). A second major leaf rust resistance QTL ( R(2)=28% and 31.5%, respectively) was located on chromosome arm 1BS close to Xgwm604 and was not associated with LTN. Additional minor QTLs for LTN (2DL, 3DL, 4BS and 5AL) and leaf rust resistance were identified. These latter QTLs might correspond to the leaf rust resistance genes Lr2 or Lr22 (2DS) and Lr14a (7BL).