ELOVL6 Genetic Variation Is Related to Insulin Sensitivity: A New Candidate Gene in Energy Metabolism

BACKGROUND: The elongase of long chain fatty acids family 6 (ELOVL6) is an enzyme that specifically catalyzes the elongation of saturated and monounsaturated fatty acids with 12, 14 and 16 carbons. ELOVL6 is expressed in lipogenic tissues and it is regulated by sterol regulatory element binding protein 1 (SREBP-1). OBJECTIVE: We investigated whether ELOVL6 genetic variation is associated with insulin sensitivity in a population from southern Spain. DESIGN: We undertook a prospective, population-based study collecting phenotypic, metabolic, nutritional and genetic information. Measurements were made of weight and height and the body mass index (BMI) was calculated. Insulin resistance was measured by homeostasis model assessment. The type of dietary fat was assessed from samples of cooking oil taken from the participants' kitchens and analyzed by gas chromatography. Five SNPs of the ELOVL6 gene were analyzed by SNPlex. RESULTS: Carriers of the minor alleles of the SNPs rs9997926 and rs6824447 had a lower risk of having high HOMA_IR, whereas carriers of the minor allele rs17041272 had a higher risk of being insulin resistant. An interaction was detected between the rs6824447 polymorphism and the intake of oil in relation with insulin resistance, such that carriers of this minor allele who consumed sunflower oil had lower HOMA_IR than those who did not have this allele (P = 0.001). CONCLUSIONS: Genetic variations in the ELOVL6 gene were associated with insulin sensitivity in this population-based study.

An antibody-based ELISA for quantification of Ani s 1, a major allergen from Anisakis simplex.

Anisakis simplex is a nematode parasite that can infect humans who have eaten raw or undercooked seafood. Larvae invading the gastrointestinal mucosa excrete/secrete proteins that are implicated in the pathogenesis of anisakiasis and can induce IgE-mediated symptoms. Since Ani s 1 is a potent secreted allergen with important clinical relevance, its measurement could assess the quality of allergenic products used in diagnosis/immunotherapy of Anisakis allergy and track the presence of A. simplex parasites in fish foodstuffs. An antibody-based ELISA for quantification of Ani s 1 has been developed based on monoclonal antibody 4F2 as capture antibody and biotin-labelled polyclonal antibodies against Ani s 1 as detection reagent. The dose-response standard curves, obtained with natural and recombinant antigens, ranged from 4 to 2000 ng/ml and were identical and parallel to that of the A. simplex extract. The linear portion of the dose-response curve with nAni s 1 was between 15 and 250 ng/ml with inter-assay and intra-assays coefficients of variation less than 20% and 10%, respectively. The assay was specific since there was no cross-reaction with other extracts (except Ascaris extracts) and was highly sensitive (detection limit of 1·8 ng/ml), being able to detect Ani s 1 in fish extracts from codfish and monkfish.

Eosinophil cationic protein is not only a distinctive eosinophil protein

We read with interest the article by Qiu et al (Thorax 2007;62:475–82). In this paper, neutrophils and eosinophils were identified using mouse anti-human neutrophil elastase and anti-eosinophil cationic protein (ECP), both monoclonal antibodies (mAbs). mAbs against ECP have been used to detect total eosinophils, but immunostaining techniques evidenced that the number of ECP+ cells was higher than the number of eosinophils.1 Recent studies show that ECP is not only a distinctive eosinophil protein, but has been found in neutrophils.1–3

Mutant prevention concentrations of fluoroquinolones for Enterobacteriaceae expressing the plasmid-carried quinolone resistance determinant qnrA1.

The influence of qnrA1 on the development of quinolone resistance in Enterobacteriaceae was evaluated by using the mutant prevention concentration parameter. The expression of qnrA1 considerably increased the mutant prevention concentration compared to strains without this gene. In the presence of qnrA1, mutations in gyrA and parC genes were easily selected to produce high levels of quinolone resistance.

A PRKAR1A Mutation Associated with Primary Pigmented Nodular Adrenocortical Disease in 12 Kindreds

CONTEXT: Primary pigmented nodular adrenocortical disease (PPNAD), a rare cause of corticotropin-independent Cushing syndrome, can be part of Carney complex (CNC), an autosomal dominant multiple neoplasia syndrome characterized by spotty skin pigmentation, cardiac myxomas, and endocrine tumors or be isolated (i). Germline PRKAR1A-inactivating mutations have been observed in both CNC and iPPNAD, but with no apparent genotype-phenotype correlation. OBJECTIVE:The objectives of the study were a detailed phenotyping for CNC manifestations in 12 kindreds bearing the same PRKAR1A mutation and a study of the consequences of the mutation and a potential founder effect. DESIGN: The study consisted of descriptive case reports. SETTING: The study was conducted at two referral centers. PATIENTS: The patients described in this study were referred for PRKAR1A gene mutation analysis because of a diagnosis of apparently iPPNAD. RESULTS: We describe a 6-bp polypyrimidine tract deletion [exon 7 IVS del (-7-->-2)] in 12 unrelated kindreds that were referred for Cushing syndrome due to PPNAD. Nine of the patients had no family history; in two, there was a family history of iPPNAD. Only one patient met the criteria for CNC. Relatives carrying the same mutation had no manifestations of CNC or PPNAD, suggesting a low penetrance of this PRKAR1A defect. A founder effect was excluded by extensive genotyping of chromosome 17 markers. CONCLUSIONS: In conclusion, a small intronic deletion of the PRKAR1A gene is a low-penetrance cause of mainly iPPNAD; it is the first PRKAR1A genetic defect to have an association with a specific phenotype.

Plasmid-mediated quinolone resistance in Australia

The aim of this study was to search for plasmid-encoded quinolone resistance determinants QnrA and QnrS in fluoroquinolone-resistant and extended-spectrum beta-lactamase (ESBL)-producing enterobacterial isolates recovered in Sydney, Australia, in 2002. Twenty-three fluoroquinolone-resistant, of which 16 were also ESBL-positive, enterobacterial and nonrelated isolates were studied. PCR with primers specific for qnrA and qnrS genes and primers specific for a series of ESBL genes were used. A qnrA gene was identified in two ESBL-positive isolates, whereas no qnrS-positive strain was found. The QnrA1 determinant was identified in an Enterobacter cloacae isolate and in a carbapenem-resistant Klebsiella pneumoniae isolate, both of which expressed the same ESBL SHV- 12. Whereas no plasmid was identified in the E. cloacae isolate, K. pneumoniae K149 possessed two conjugative plasmids, one that harbored the qnrA and bla (SHV)-12 genes whereas the other expressed the carbapenemase gene bla (IMP-4). The qnrA gene, was located in both cases downstream of the orf513 recombinase gene and upstream of the qnrA1 gene, a structure identical to that found in sul1-type integron In36 and qnrA-positive strains from Shanghai, China. However, the gene cassettes of the sul1-type integrons were different. This study identified the first plasmid-mediated quinolone resistance determinant in Enterobacteriaceae in Australia.

Nosocomial bacteremia due to an as yet unclassified acinetobacter genomic species 17-like strain.

We describe a case of bacteremia due to an as yet unclassified Acinetobacter genomic species 17-like strain. The recognition of this microorganism as non-Acinetobacter baumannii may have important epidemiological implications, as it relieves the hospital of the implementation of barrier precautions for patients infected or colonized as may be necessary with a multiresistant A. baumannii epidemic.

A Change in the Epidemiology of Infections Due to Extended-Spectrum b-Lactamase–Producing Organisms

Extended-spectrum β-lactamases (ESBLs) form a heterogeneous group that share the property of hydrolytic activity against the oxyimino-β-lactams while remaining susceptible to inhibition by β-lactamase inhibitors, such as clavulanic acid. From a clinical point of view, they are important because they confer resistance to penicillins, aztreonam, and cephalosporins, and ESBL-producing organisms are typically also resistant to aminoglycosides, trimethoprim-sulfamethoxazole, and quinolones [1]. Until recently, the main problem posed by ESBLs was related to nosocomial outbreaks caused by ESBL-producing Klebsiella species. These outbreaks are usually clonal, the strains are mainly spread through cross-transmission, and the risk factors are similar to those found for other multidrug-resistant nosocomial pathogens [2]. In Europe and the United States, most ESBL-producing Klebsiella isolates harbored enzymes belonging to the TEM and SHV families [3]. Detection of colonized patients by performing surveillance cultures within affected units, isolation precautions for colonized patients, and restriction of oxyimino-β-lactam use are frequently useful for the control of these outbreaks [1]. There is no evidence that hospital-acquired ESBL-producing klebsiellae are decreasing in importance—in fact, data from the Centers for Disease Control and Prevention show that 20.6% of Klebsiella pneumoniae isolates from United States intensive care units in 2003 were probable producers of ESBL [4]. This represented a 47% increase, compared with the preceding 5 years. However, during the last few years, an impressive increase in the number of ESBL-producing Escherichia coli (and, less frequently, other Enterobacteriaceae) is being described in several parts of the world [5–8]. This emergent phenomenon shows some differences from the problem posed by Klebsiella species; many of these ESBL-producing E. coli are isolated …

Bacteremia due to extended-spectrum beta-lactamase-producing Escherichia coli in the CTX-M era: a new clinical challenge.

Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, particularly those producing CTX-M types of ESBL, are emerging pathogens. Bacteremia caused by these organisms represents a clinical challenge, because the organisms are frequently resistant to the antimicrobials recommended for treatment of patients with suspected E. coli sepsis. METHODS:A cohort study was performed that included all episodes of bloodstream infection due to ESBL-producing E. coli during the period from January 2001 through March 2005. Data on predisposing factors, clinical presentation, and outcome were collected. ESBLs were characterized using isoelectric focusing, polymerase chain reaction, and sequencing. RESULTS: Forty-three episodes (8.8% of cases of bacteremia due to E. coli) were included; 70% of the isolates produced a CTX-M type of ESBL. The most frequent origins of infection were the urinary (46%) and biliary tracts (21%). Acquisition was nosocomial in 21 cases (49%), health care associated in 14 cases (32%), and strictly community acquired in 8 cases (19%). Thirty-eight percent and 25% of patients had obstructive diseases of the urinary and biliary tracts, respectively, and 38% had recently received antimicrobials. Nine patients (21%) died. Compared with beta-lactam/beta-lactamase-inhibitor and carbapenem-based regimens, empirical therapy with cephalosporins or fluoroquinolones was associated with a higher mortality rate (9% vs. 35%; P=.05) and needed to be changed more frequently (24% vs. 78%; P=.001). CONCLUSIONS: ESBL-producing E. coli is a significant cause of bloodstream infection in hospitalized and nonhospitalized patients in the context of the emergence of CTX-M enzymes. Empirical treatment of sepsis potentially caused by E. coli may need to be reconsidered in areas where such ESBL-producing isolates are present.

Novel MLPA procedure using self-designed probes allows comprehensive analysis for CNVs of the genes involved in Hirschsprung disease.

Background: Hirschsprung disease is characterized by the absence of intramural ganglion cells in the enteric plexuses, due to a fail during enteric nervous system formation. Hirschsprung has a complex genetic aetiology and mutations in several genes have been related to the disease. There is a clear predominance of missense/nonsense mutations in these genes whereas copy number variations (CNVs) have been seldom described, probably due to the limitations of conventional techniques usually employed for mutational analysis. In this study, we have looked for CNVs in some of the genes related to Hirschsprung (EDNRB, GFRA1, NRTN and PHOX2B) using the Multiple Ligation-dependent Probe Amplification (MLPA) approach. Methods: CNVs screening was performed in 208 HSCR patients using a self-designed set of MLPA probes, covering the coding region of those genes. Results: A deletion comprising the first 4 exons in GFRA1 gene was detected in 2 sporadic HSCR patients and in silico approaches have shown that the critical translation initiation signal in the mutant gene was abolished. In this study, we have been able to validate the reliability of this technique for CNVs screening in HSCR. Conclusions: The implemented MLPA based technique presented here allows CNV analysis of genes involved in HSCR that have not been not previously evaluated. Our results indicate that CNVs could be implicated in the pathogenesis of HSCR, although they seem to be an uncommon molecular cause of HSCR.

Outcome after relapse of acute lymphoblastic leukemia in adult patients included in four consecutive risk-adapted trials by the PETHEMA Study Group

BACKGROUND About one half of adults with acute lymphoblastic leukemia are not cured of the disease and ultimately die. The objective of this study was to explore the factors influencing the outcome of adult patients with relapsed acute lymphoblastic leukemia. DESIGN AND METHODS. We analyzed the characteristics, the outcome and the prognostic factors for survival after first relapse in a series of 263 adult patients with acute lymphoblastic leukemia (excluding those with mature B-cell acute lymphoblastic leukemia) prospectively enrolled in four consecutive risk-adapted PETHEMA trials. RESULTS. The median overall survival after relapse was 4.5 months (95% CI, 4-5 months) with a 5-year overall survival of 10% (95% CI, 8%-12%); 45% of patients receiving intensive second-line treatment achieved a second complete remission and 22% (95% CI, 14%-30%) of them remained disease free at 5 years. Factors predicting a good outcome after rescue therapy were age less than 30 years (2-year overall survival of 21% versus 10% for those over 30 years old; P<0.022) and a first remission lasting more than 2 years (2-year overall survival of 36% versus 17% among those with a shorter first remission; P<0.001). Patients under 30 years old whose first complete remission lasted longer than 2 years had a 5-year overall survival of 38% (95% CI, 23%-53%) and a 5-year disease-free survival of 53% (95% CI, 34%-72%). CONCLUSIONS The prognosis of adult patients with acute lymphoblastic leukemia who relapse is poor. Those aged less than 30 years with a first complete remission lasting longer than 2 years have reasonable possibilities of becoming long-term survivors while patients over this age or those who relapse early cannot be successfully rescued using the therapies currently available.

Citrulina plasmática como marcador de pérdida de masa enterocitaria en la enfermedad celíaca en la infancia

Introduction: Plasma citrulline is not incorporated in endogenous or exogenous proteins so it is a theoretical marker of villous atrophy. Our aim was to correlate plasma citrulline levels with severity of villous atrophy inceliac patients. Methods: Observational case-control study longitudinal in children 16 month-old to 14 year-old: 48 with untreated celiac disease, 9 celiac children under gluten free diet and 35 non-celiac healthy children. Plasma amino acids concentration is determined, expressed in μmol/L, and so are other clinical and analytical data. Results: No statistically significative difference found in the referring to BMI, age or renal function. Small increase in fecal fat in celiac children. Citrulline, arginine and glutamine are significantly lower in cases (17.7 μmol/l, 38.7 μmol/l, 479.6 μmol/l respectively) than in controls (28.9 μmol/l, 56.2 μmol/l, 563.7 μmol/l). Citrulline levels are significantly lower in the severe degrees of atrophy than in mild ones (13.8 μmol/l vs. 19.7 μmol/l, p < 0.05), not happening so with rest of amminoacids. Summary: Postabsortive mean of plasma citrulline is a good marker of reduction in enterocyte mass in celiac patients with villous atrophy; secondary reduction in plasma arginine too. Just a small histological alteration in intestinal biopsy is enough to differentiate citrulline in cases and controls and besides it can be seen that high levels of atrophy present with lower plasma citrulline.

Serosurvey Study of Toscana Virus in Domestic Animals, Granada, Spain

Toscana virus (TOSV) is transmitted by infected sandflies. In Mediterranean countries, TOSV is one of the major viral pathogens involved in aseptic meningitis and meningoencephalitis in humans. It remains unclear if there are animal reservoirs able to maintain the virus through the cold months of the year, when the vector is not circulating. From May to October of 2006 and 2007, we conducted a serosurvey study on domestic animals from Granada province (southern Spain). TOSV was investigated in 1186 serum samples from horses, goats, pigs, cats, dogs, sheep, and cows by serology (indirect fluorescence assay), viral culture, and RT-polymerase chain reaction. Specific anti-TOSV antibodies were detected in 429 (36.2%) serum samples. The highest seropositivity rates were observed in cats (59.6%) and dogs (48.3%). These results suggest that an important percentage of the domestic animals have been infected by TOSV. Significantly different seroprevalence rates were detected in goats among distinct geographical areas. All viral cultures were negative. TOSV was detected by RT-polymerase chain reaction in only one serum sample from a goat. Thus, the studied animals do not seem to act as reservoirs for TOSV; otherwise, they could be amplifying hosts for the virus.

Granada Virus: a Natural Phlebovirus Reassortant of the Sandfly Fever Naples Serocomplex with Low Seroprevalence in Humans

A new member of the phlebovirus genus, tentatively named Granada virus, was detected in sandflies collected in Spain. By showing the presence of specific neutralizing antibodies in human serum collected in Granada, we show that Granada virus infects humans. The analysis of the complete genome of Granada virus revealed that this agent is likely to be a natural reassortant of the recently described Massilia virus (donor of the long and short segments) with ayet unidentified phlebovirus (donor of the medium segment)

The value of metabolic imaging to predict tumour response after chemoradiation in locally advanced rectal cancer

Background: We aim to investigate the possibility of using 18F-positron emission tomography/computer tomography (PET-CT) to predict the histopathologic response in locally advanced rectal cancer (LARC) treated with preoperative chemoradiation (CRT). Methods: The study included 50 patients with LARC treated with preoperative CRT. All patients were evaluated by PET-CT before and after CRT, and results were compared to histopathologic response quantified by tumour regression grade (patients with TRG 1-2 being defined as responders and patients with grade 3-5 as non-responders). Furthermore, the predictive value of metabolic imaging for pathologic complete response (ypCR) was investigated. Results: Responders and non-responders showed statistically significant differences according to Mandard's criteria for maximum standardized uptake value (SUVmax) before and after CRT with a specificity of 76,6% and a positive predictive value of 66,7%. Furthermore, SUVmax values after CRT were able to differentiate patients with ypCR with a sensitivity of 63% and a specificity of 74,4% (positive predictive value 41,2% and negative predictive value 87,9%); This rather low sensitivity and specificity determined that PET-CT was only able to distinguish 7 cases of ypCR from a total of 11 patients. Conclusions: We conclude that 18-F PET-CT performed five to seven weeks after the end of CRT can visualise functional tumour response in LARC. In contrast, metabolic imaging with 18-F PET-CT is not able to predict patients with ypCR accurately