The Arabidopsis chromatin regulator MOM1 is a negative component of the defense priming induced by AZA, BABA and PIP.

In plants, the establishment of broad and long-lasting immunity is based on programs that control systemic resistance and immunological memory or "priming". Despite not showing activated defenses, a primed plant induces a more efficient response to recurrent infections. Priming might involve chromatin modifications that allow a faster/stronger activation of defense genes. The Arabidopsis chromatin regulator "Morpheus Molecule 1" (MOM1) has been recently suggested as a priming factor affecting the expression of immune receptor genes. Here, we show that mom1 mutants exacerbate the root growth inhibition response triggered by the key defense priming inducers azelaic acid (AZA), ß-aminobutyric acid (BABA) and pipecolic acid (PIP). Conversely, mom1 mutants complemented with a minimal version of MOM1 (miniMOM1 plants) are insensitive. Moreover, miniMOM1 is unable to induce systemic resistance against Pseudomonas sp. in response to these inducers. Importantly, AZA, BABA and PIP treatments reduce the MOM1 expression, but not miniMOM1 transcript levels, in systemic tissues. Consistently, several MOM1-regulated immune receptor genes are upregulated during the activation of systemic resistance in WT plants, while this effect is not observed in miniMOM1. Taken together, our results position MOM1 as a chromatin factor that negatively regulates the defense priming induced by AZA, BABA and PIP.

Shiga toxin-producing Escherichia coli in beef retail markets from Argentina.

Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens that cause mild or serious diseases and can lead to people death. This study reports the prevalence and characteristics of STEC O157 and non-O157 in commercial ground beef and environmental samples, including meat table, knife, meat mincing machine, and manipulator hands (n = 450) obtained from 90 retail markets over a nine-month period. The STEC isolates were serotyped and virulence genes as stx (Shiga toxin), rfb(O157)] (O157 lipopolysaccharide), fliC(H7) (H7 flagellin), eae (intimin), ehxA (enterohemolysin) and saa (STEC autoagglutinating adhesin), were determined. STEC O157 were identified in 23 (25.5%) beef samples and 16 (4.4%) environmental samples, while STEC non-O157 were present in 47 (52.2%) and 182 (50.5%), respectively. Among 54 strains isolated, 17 were STEC O157:H7 and 37 were STEC non-O157. The prevalent genotype for O157 was stx(2)/eae/ehxA/fliC(H7) (83.4%), and for STEC non-O157 the most frequent ones were stx(1)/stx(2)/saa/ehxA (29.7%); stx(2) (29.7%); and stx(2)/saa/ehxA (27%). None of the STEC non-O157 strains were eae-positive. Besides O157:H7, other 20 different serotypes were identified, being O8:H19, O178:H19, and O174:H28 the prevalent. Strains belonging to the same serotype could be isolated from different sources of the same retail market. Also, the same serotype could be detected in different stores. In conclusion, screening techniques are increasingly sensitive, but the isolation of STEC non-O157 is still a challenge. Moreover, with the results obtained from the present work, although more studies are needed, cross-contamination between meat and the environment could be suspected.

Pneumonia in allogeneic stem cell transplantation recipients: a multicenter prospective study.

Pneumonia is a common cause of mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT) but updated and prospective information is partial. The aim of this nationwide prospective study is to determine the current epidemiology, etiology, and outcome of pneumonia in allo-HSCT recipients. From September-2003 to November-2005, 112 episodes in 427 consecutive allo-HSCT recipients were included (incidence 52.2 per 100 allo-HSCT/yr), and 72 of them (64.3%) were microbiologically defined pneumonia. Bacterial pneumonia (44.4%) was more frequent than fungal (29.2%) and viral pneumonia (19.4%). The most frequent microorganisms in each group were: Escherichia coli (n = 7, 8.9%), Streptococcus pneumoniae (n = 4, 5.0%), cytomegalovirus (n = 12, 15.4%), and Aspergillus spp. (n = 12, 15.4%). The development of pneumonia and chronic graft-versus-host disease (GVHD) was associated with increased mortality after allo-HSCT, and the probability of survival was significantly lower in patients that had at least one pneumonia episode (p < 0.01). Pneumonia development in the first 100 d after transplantation, fungal etiology, GVHD, acute respiratory failure, and septic shock were associated with increased mortality after pneumonia. Our results show that pneumonia remains a frequent infectious complication after allo-HSCT, contributing to significant mortality, and provide a large current experience with the incidence, etiology and outcome of pneumonia in these patients.

Valganciclovir as pre-emptive therapy for cytomegalovirus infection in allogeneic haematopoietic stem cell transplant recipients.

BACKGROUND: In haematopoietic stem cell transplant (HSCT) recipients, cytomegalovirus (CMV) infection contributes significantly to morbidity and mortality in both the early and late post-transplant period. Ganciclovir (GCV) is the treatment of choice for CMV, but requires intravenous administration, a fact that complicates its long-term use. Oral valganciclovir (VGCV) and intravenous GCV were recently shown to have similar efficacy for pre-emptive CMV treatment in solid organ transplant recipients, but relatively limited data are available in HSCT recipients. The objectives of this study were to compare the efficacy of VGCV versus intravenous GCV or foscarnet (FOS) for pre-emptive therapy of active CMV infection in allogeneic HSCT and to determine the incidence of adverse effects and relapses. METHODS: This was a 2-year prospective, comparative cohort study in which 237 episodes of pre-emptive therapy for active CMV infection were collected in 166 allogeneic HSCT recipients out of 717 included in the Spanish Network for Research on Infection in Transplantation (RESITRA/REIPI) database. Intravenous GCV was the first-line treatment in 112 episodes, intravenous FOS in 38 episodes, and oral VGCV in 87 episodes. RESULTS: VGCV was used as pre-emptive therapy for active CMV infection in 87 episodes. Excluding episodes considered as relapse, VGCV was as successful (91.4% [74/81]) as GCV (83.7% [87/14]) or FOS (75.8% [25/33]). In the VGCV arm, 7 (8.6%) cases were considered treatment failures: 4 (4.9%) because of adverse events, 1 (1.2%) due to persistent viral activity and 2 (2.5%) based on clinical decision. There were also 6 (7.4%) cases of recurrent infection. No statistically significant differences were found when compared to GCV or FOS. CONCLUSIONS: In allogeneic HSCT recipients, VGCV seemed effective and safe in the pre-emptive therapy of active CMV infection.

Update on bacteraemia in oncology and hematology.

The present article is an update of the literature on bacteraemia in onco-hematologic patients. A multidisciplinary group of Spanish physicians with an interest in this field selected the most important papers published recently. Papers from the fields of basic science, epidemiology, causative microorganisms and clinical syndromes are discussed. Important aspects of these studies include the assessment of different strategies in the management of fever in neutropenic patients and the validation of specific scores. Moreover, early identification of patients at risk of bacterial and of multi-drug resistant infections is a topic of increasing interest.

Comparison of CHOP treatment with specific short-intensive chemotherapy in AIDS-related Burkitt's lymphoma or leukemia.

BACKGROUND AND OBJECTIVE: AIDS-related Burkitt's lymphoma or leukemia (BLL) is increasingly treated with specific and intensive multiagent schedules. This retrospective study aimed to compare the results of CHOP with those from two protocols (PETHEMA-LAL3/97 and BURKIMAB) of specific therapy in Spain. PATIENTS AND METHODS: Patients from Group A (n=31) received 6 standard CHOP cycles every 3 weeks. Patients from group B (n=44) received six multiagent cycles including high-dose methotrexate and high-dose cytarabine. The response to therapy, disease-free survival and overall survival (OS) were compared in the two groups. RESULTS: Both groups were comparable for the main clinical and biological parameters at diagnosis except for risk activity, previous HAART, bone marrow involvement, bulky disease and extranodal involved sites. Complete remission (CR) was achieved in 10 out of 31 (32%) patients in group A and 28 out of 44 (67%) patients in group B (P=.005). After a median (range) follow-up of 70 (26-139) and 17 (1-134) months, the 5-year (95% CI) DFS probability was 87% (64%-100%) for group A and 70% (51%-89%) for group B (P=.374), and the 5-year (95% CI) OS was 27% (10%-43%) for Group A and 57% (40%-74%) for group B (P=.028). Multivariate analyses showed that specific therapy was associated with an improved CR and OS. CONCLUSIONS: In AIDS-related BLL short intensive specific chemotherapy is feasible, with higher remission rate and improved survival than that obtained with CHOP-based regimens.

Prediction of response to pegylated interferon plus ribavirin by IL28B gene variation in patients coinfected with HIV and hepatitis C virus.

BACKGROUND: Variation in the IL28B gene is associated with sustained virologic response (SVR) to pegylated interferon plus ribavirin in hepatitis C virus (HCV)-monoinfected patients with genotype 1. Data on other genotypes and on patients coinfected with human immunodeficiency virus (HIV) and HCV are more limited. We aimed to assess the predictive ability of variations in the single-nucleotide polymorphism rs12979860 for SVR in HIV/HCV-coinfected patients, regardless of HCV genotype. METHODS: The rs12979860 genotype was determined by polymerase chain reaction in 154 patients who had received therapy against HCV with pegylated interferon plus ribavirin. RESULTS: rs12979860 genotype was TT in 20 patients (13%), TC in 66 patients (43%), and CC in 68 patients (44%). Rates of SVR in patients with genotype CC and in those with genotype TC or TT, according to HCV genotype, were, respectively, 50% and 17% (P < .001) in patients with genotype 1, 80% and 25% (P = .027) in patients with genotype 4, and 93% and 77% (P = .115) in patients with genotype 3. The median (interquartile range) low-density lipoprotein cholesterol level in patients with rs12979860 CC was 89 mg/dL (73-120 mg/dL) versus 75 mg/dL (55-91 mg/dL) (P = .001) in those with TC or TT. Independent predictors of SVR were HCV genotype 2-3 (odds ratio [OR], 13.98; 95% confidence interval [CI], 4.87-40.1; P < .001), rs12979860 CC (OR, 5.05; 95% CI, 2.04-12.5; P < .001), baseline plasma HCV RNA load of < or =600,000 IU/mL (OR, 1.99; 95% CI, 1.18- 3.34; P = .009), and female sex (OR, 4.28; 95% CI, 1.08-16.96; P = .039). CONCLUSIONS: IL28B gene variations independently predict SVR in HIV/HCV-coinfected patients with HCV genotype 1 and non-genotype 1 HCV infection. The association between rs12979860 and plasma low-density lipoprotein cholesterol suggests that the system low-density lipoprotein ligand/receptor might be involved in the effect of this genotype.

Interobserver concordance in the assessment of liver fibrosis in HIV/HCV-coinfected patients using transient elastometry.

OBJECTIVES: Although the reproducibility of transient elastometry (TE) in hepatitis C virus (HCV)-monoinfected patients seems to be high, this may not be the case in HIV/HCV-coinfected patients because of different degrees of steatosis and/or inflammation. This study was aimed to determine the interobserver concordance of TE measurements in HIV/HCV-coinfected patients. METHODS: A total of 188 patients were evaluated in a cross-sectional, prospective study in two hospitals. The interobserver variability of TE results and the rate of unequal classification of significant fibrosis (cutoff value = 7.2 kPa) and cirrhosis (cutoff value = 14.6 kPa) for two observers were evaluated. RESULTS: The values of liver stiffness (LS) for two observers highly correlated [intraclass correlation index = 0.976; 95% confidence interval (CI): 0.968-0.982]. The kappa indexes for the concordance of patient classification were 0.60 for significant fibrosis and 0.89 for cirrhosis. Using two cutoff points to diagnose or rule out significant fibrosis (LS >or=9 kPa or <6 kPa) yielded a kappa index of 0.96, but 46% of patients were not classified. Covariables that influenced the interobserver agreement were a high interquartile range in the determination (adjusted odd ratio: 0.189; 95% CI: 0.087-0.411; P = 0.001) and elevated levels of triglycerides (adjusted odd ratio: 1.004; 95% CI: 1.000-1.008; P = 0.031). CONCLUSION: TE measurement is an observer-independent method to evaluate LS in HIV/HCV coinfected patients. The concordance of the classification of mild-to-severe fibrosis is good and for the diagnosis of cirrhosis is excellent. Lower interquartile ranges and triglyceride levels lead to a higher interobserver agreement.

The use of transient elastometry for assessing liver fibrosis in patients with HIV and hepatitis C virus coinfection.

BACKGROUND: Transient elastometry (TE) is accurate for detecting significant liver fibrosis and cirrhosis in hepatitis C virus (HCV)-monoinfected patients. However, this procedure has been insufficiently validated in patients with human immunodeficiency virus (HIV) and HCV coinfection. The purpose of this study was to validate reported cutoff values of TE that discriminate significant liver fibrosis and cirrhosis in HIV-HCV-coinfected subjects. METHODS: Liver stiffness measurements were obtained for 169 HIV-HCV-coinfected adult patients who had undergone a liver biopsy or who had received a nonhistologic diagnosis of cirrhosis within 12 months before or after a liver stiffness measurement. Patients had received no prior therapy for HCV infection. RESULTS: TE measurements ranged from 3.6 kPa to 75 kPa. The area under the receiver operating characteristic curve was 0.87 (95% confidence interval, 0.84-0.93) for significant liver fibrosis and 0.95 (95% confidence interval, 0.92-0.99) for cirrhosis. To diagnose significant liver fibrosis, a cutoff value of 7.2 kPa was associated with a positive predictive value of 88% and a negative predictive value of 75%. Thirty-four patients (20%) were misclassified when this cutoff value was used. Thirteen (24%) of 54 patients with liver stiffness values <7.2 kPa had significant liver fibrosis detected by liver biopsy. To diagnose cirrhosis, a cutoff value of 14.6 kPa was associated with a positive predictive value of 86% and a negative predictive value of 94%. Thus, 13 patients (10%) had disease that was misclassified using this cutoff value. CONCLUSIONS: We found that the diagnostic accuracy of TE was high for detecting cirrhosis and good for diagnosis of significant liver fibrosis. However, the performance of TE was low for discriminating mild fibrosis from significant liver fibrosis, which might limit the applicability of this technique in clinical practice.

Failure of cetirizine to prevent nevirapine-associated rash: a double-blind placebo-controlled trial for the GESIDA 26/01 Study.

OBJECTIVES: Rash is the most frequent adverse event associated with nevirapine. The use of antihistamines remains unclear in this setting. A double-blind placebo-controlled study was performed to evaluate the efficacy of cetirizine in the prevention of nevirapine rash. METHODS: A multicenter, randomized, double-blind, placebo-controlled clinical trial with cetirizine (10 mg/d x 30 days) was conducted. Inclusion criteria were HIV-1 infection and nevirapine therapy started with any CD4 cell count or plasma viral load and without simultaneous use of abacavir, cotrimoxazole, or rifampin. Clinical follow-up was performed at 15, 30, and 90 days. RESULTS: Two hundred seventeen evaluable patients were enrolled (107 patients receiving cetirizine and 110 patients receiving placebo), 32.3% of whom were women. The median baseline CD4 cell count and plasma viral load were 341 cells/mm and 11,000 copies/mL, respectively. Overall, 29 rashes (13.4%) were detected: 16 (15.0%) in the cetirizine group and 13 (11.8%) in the placebo group (odds ratio [OR] = 1.31, 95% confidence interval [CI]: 0.60-2.88; P = 0.50). The incidence of moderate to severe rashes leading to nevirapine withdrawal was 10.3% (11 of 107 patients) in the cetirizine group and 7.3% (8 of 110 patients) in the placebo group (OR = 1.46, 95% CI: 0.52-4.18; P = 0.43). Adverse events leading to withdrawal of therapy appeared in 14 patients (13.1%) from the cetirizine group and 10 (9.1%) from the placebo group (P = 0.34). CONCLUSION: Cetirizine does not prevent the incidence or affect the severity of nevirapine-associated rash.