A microsatellite linkage map for the cultivated strawberry (Fragaria × ananassa) suggests extensive regions of homozygosity in the genome that may have resulted from breeding and selection.

The linkage maps of the cultivated strawberry, Fragaria × ananassa (2n = 8x = 56) that have been reported to date have been developed predominantly from AFLPs, along with supplementation with transferrable microsatellite (SSR) markers. For the investigation of the inheritance of morphological characters in the cultivated strawberry and for the development of tools for marker-assisted breeding and selection, it is desirable to populate maps of the genome with an abundance of transferrable molecular markers such as microsatellites (SSRs) and gene-specific markers. Exploiting the recent release of the genome sequence of the diploid F. vesca, and the publication of an extensive number of polymorphic SSR markers for the genus Fragaria, we have extended the linkage map of the 'Redgauntlet' × 'Hapil' (RG × H) mapping population to include a further 330 loci, generated from 160 primer pairs, to create a linkage map for F. × ananassa containing 549 loci, 490 of which are transferrable SSR or gene-specific markers. The map covers 2140.3 cM in the expected 28 linkage groups for an integrated map (where one group is composed of two separate male and female maps), which represents an estimated 91% of the cultivated strawberry genome. Despite the relative saturation of the linkage map on the majority of linkage groups, regions of apparent extensive homozygosity were identified in the genomes of 'Redgauntlet' and 'Hapil' which may be indicative of allele fixation during the breeding and selection of modern F. × ananassa cultivars. The genomes of the octoploid and diploid Fragaria are largely collinear, but through comparison of mapped markers on the RG × H linkage map to their positions on the genome sequence of F. vesca, a number of inversions were identified that may have occurred before the polyploidisation event that led to the evolution of the modern octoploid strawberry species.

[Intestinal obstruction secondary to endometriosis of the colon]. / Obstrucción intestinal secundaria a endometriosis de colon.

Endometriosis is defined as the presence of endometrial tissue outside the uterine cavity. Although in most cases it is a benign disorder, it may be aggressive producing local invasion and even metastasis. Endometrial implantation has been reported in many organs including the small and large intestine leading to acute or chronic symptomatology. The clinical picture of intestinal obstruction is due to stenosis produced by the adherences or fibrosis caused by endometrial sloughing. We present a case of intestinal endometriosis with clinical manifestation of obstruction of the colon. This disorder should be included in the differential diagnosis of fertile females presenting intestinal obstruction with no other predisposing factors.

[Takayasu arteritis; IV. Absence of autoantibodies and coagulation/fibrinolysis abnormalities]. / Arteritis de Takayasu; IV. Ausencia de autoanticuerpos y anomalías de la coagulación/fibrinolisis.

The etiopathogenesis of the non-specific arteritis known as Takayasu's arteritis, an inflammatory occlusive disease of the aorta and its main branches, is unknown. We searched for abnormalities in clotting and fibrinolytic systems, as well as the presence of non-organ specific autoantibodies, including those potentially reactive with vascular endothelium, in 21 untreated patients. There were only minor abnormalities in coagulation and fibrinolysis in a few patients, and the occasional presence of non-organ specific antibodies, including antiphospholipid antibodies. The findings had no clinical relevance. This study suggests that there is no support for a significative role of humoral immunity, coagulation and fibrinolysis in the pathogenesis of Takayasu's arteritis.

Relationship between bacterial load, morbidity and cagA gene in patients infected by Helicobacter pylori.

One hundred and seventy-six biopsies of the gastric corpus and antrum from 97 patients were processed using classical and molecular methods in order to study the relationship between the factor cagA of Helicobacter pylori, bacterial load and morbidity. Bacterial load in patients with cagA was greater than in patients without it, both in the antrum and corpus (p<0.01). There was a statistically significant association between cagA and consumption of proton pump inhibitors (adjusted odds ratio 3.11). Haemorrhage of the upper digestive tract was more associated with bacterial load than with the cagA gene (adjusted odds ratio 2.34 and 1.12, respectively), but none of these associations yielded statistical significance.

HLA-DR6 (possibly DRB1*1301) is associated with susceptibility to Takayasu arteritis in Mexicans.

Takayasu arteritis is characterized by a "pulseless" condition and occurs frequently in young females from Asian and South American countries. This disease has been found to be linked with major histocompatibility complex (MHC) antigens in Japanese individuals. In the present study we compared gene frequencies of class I, class II, and class III MHC genotypes in patients with Takayasu arteritis and ethnically matched healthy controls. Serological typing was confirmed by molecular typing at the DNA level. We found significant increases in the frequencies of human leucocyte antigen (HLA)-DR6 and HLA-B62 in patients compared to the healthy controls (P corrected [C] = 0.0007, relative risk [RR] = 5.08; PC = 0.05, RR = 3.13 respectively). However, since the number of patients was considerably lower than the number of controls this can be considered as a tendency and not a true association. On the other hand, we found a significantly decreased frequency of HLA-DR4 in patients compared to healthy controls (PC = 0.04, RR = 0.34). At the DNA level, all DR6-positive individuals were HLA-DRB1*1301 whereas controls were HLA-DRB1*1301 (4.2%). Takayasu arteritis in Mexicans is probably associated with the HLA-DR6 (DRB1*1301) gene.

Development of quinolone-resistant strains of Escherichia coli in stools of patients with cirrhosis undergoing norfloxacin prophylaxis: clinical consequences.

BACKGROUND/AIM: Norfloxacin prophylaxis decreases the incidence of bacterial infections in high-risk cirrhotic patients, but may promote the development of quinolone-resistant gram-negative bacteria in stools, and eventually lead to infections due to these bacteria. The aim of the study was to evaluate the prevalence of quinolone-resistant strains of E. coli in stools on admission, and the characteristics of any nosocomial infections. METHODS: Eighty-three consecutively hospitalized cirrhotic patients were included in this prospective study. The presence of quinolone-resistant strains of E. coli in stools on admission, and the characteristics of any nosocomial infections were recorded. RESULTS: Fourteen out of 83 patients (16.8%) showed quinolone-resistant E. coli in stools (Group I), and 69 did not (Group II). Thirteen out of 14 from Group I (92.8%) and 17/69 (24.6) from Group II had received primary or secondary prophylaxis with norfloxacin (p<0.001). During hospitalization, 12/12 (100%) of patients from Group I and 25/66 (37.8%) of patients from Group II underwent norfloxacin prophylaxis. Three bacterial infections in patients from Group I, 3 from Group II patients receiving norfloxacin and 16 from Group II patients not receiving norfloxacin were recorded (p<0.05). No infections due to quinolone-resistant E. coli were observed in patients colonized with these bacteria. Treatment with norfloxacin induced the development of quinolone-resistant E. coli in 6/14 (42.8%) patients in a mean time of 18.5+/-9.8 days. CONCLUSIONS: The development of quinolone-resistant strains of E. coli is significantly associated with previous administration of norfloxacin prophylaxis. However, in our series this fact is not associated with an increased incidence of quinolone-resistant E. coli or other gram-negative infections.