SETD2 and histone H3 lysine 36 methylation deficiency in advanced systemic mastocytosis

The molecular basis of advanced systemic mastocytosis (SM) is not fully understood and despite novel therapies the prognosis remains dismal. Exome sequencing of an index-patient with mast cell leukemia (MCL) uncovered biallelic loss-of-function mutations in the SETD2 histone methyltransferase gene. Copy-neutral loss-of-heterozygosity at 3p21.3 (where SETD2 maps) was subsequently found in SM patients and prompted us to undertake an in-depth analysis of SETD2 copy number, mutation status, transcript expression and methylation levels, as well as functional studies in the HMC-1 cell line and in a validation cohort of 57 additional cases with SM, including MCL, aggressive SM and indolent SM. Reduced or no SETD2 protein expression—and consequently, H3K36 trimethylation—was found in all cases and inversely correlated with disease aggressiveness. Proteasome inhibition rescued SETD2 expression and H3K36 trimethylation and resulted in marked accumulation of ubiquitinated SETD2 in SETD2-deficient patients but not in patients with near-normal SETD2 expression. Bortezomib and, to a lesser extent, AZD1775 alone or in combination with midostaurin induced apoptosis and reduced clonogenic growth of HMC-1 cells and of neoplastic mast cells from advanced SM patients. Our findings may have implications for prognostication of SM patients and for the development of improved treatment approaches in advanced SM.

Modification of Ni-Rich FCG NMC and NCA Cathodes by Atomic Layer Deposition: Preventing Surface Phase Transitions for High-Voltage Lithium-Ion Batteries

The energy density of current lithium-ion batteries (LIBs) based on layered LiMO2 cathodes (M = Ni, Mn, Co: NMC; M = Ni, Co, Al: NCA) needs to be improved significantly in order to compete with internal combustion engines and allow for widespread implementation of electric vehicles (EVs). In this report, we show that atomic layer deposition (ALD) of titania (TiO2) and alumina (Al2O3) on Ni-rich FCG NMC and NCA active material particles could substantially improve LIB performance and allow for increased upper cutoff voltage (UCV) during charging, which delivers significantly increased specific energy utilization. Our results show that Al2O3 coating improved the NMC cycling performance by 40% and the NCA cycling performance by 34% at 1 C/-1 C with respectively 4.35 V and 4.4 V UCV in 2 Ah pouch cells. High resolution TEM/SAED structural characterization revealed that Al2O3 coatings prevented surface-initiated layered-to-spinel phase transitions in coated materials which were prevalent in uncoated materials. EIS confirmed that Al2O3-coated materials had significantly lower increase in the charge transfer component of impedance during cycling. The ability to mitigate degradation mechanisms for Ni-rich NMC and NCA illustrated in this report provides insight into a method to enable the performance of high-voltage LIBs.

Development and evaluation of a secondary reference panel for BCR-ABL1 quantification on the International Scale

Molecular monitoring of chronic myeloid leukemia patients using robust BCR-ABL1 tests standardized to the International Scale (IS) is key to proper disease management, especially when treatment cessation is considered. Most laboratories currently use a time-consuming sample exchange process with reference laboratories for IS calibration. A World Health Organization (WHO) BCR-ABL1 reference panel was developed (MR¹–MR⁴), but access to the material is limited. In this study, we describe the development of the first cell-based secondary reference panel that is traceable to and faithfully replicates the WHO panel, with an additional MR^4.5 level. The secondary panel was calibrated to IS using digital PCR with ABL1, BCR and GUSB as reference genes and evaluated by 44 laboratories worldwide. Interestingly, we found that >40% of BCR-ABL1 assays showed signs of inadequate optimization such as poor linearity and suboptimal PCR efficiency. Nonetheless, when optimized sample inputs were used, >60% demonstrated satisfactory IS accuracy, precision and/or MR^4.5 sensitivity, and 58% obtained IS conversion factors from the secondary reference concordant with their current values. Correlation analysis indicated no significant alterations in %BCR-ABL1 results caused by different assay configurations. More assays achieved good precision and/or sensitivity than IS accuracy, indicating the need for better IS calibration mechanisms.

Cow's milk and rice fermented with Lactobacillus paracasei CBA L74 prevent infectious diseases in children: A randomized controlled trial

BACKGROUND & AIM

Fermented foods have been proposed for the prevention of infectious diseases. We evaluated the efficacy of fermented foods in reducing common infectious diseases (CIDs) in children attending daycare.

METHODS

Prospective randomized, double-blind, placebo-controlled trial (registered under Clinical Trials.gov identifier NCT01909128) on healthy children (aged 12-48 months) consuming daily cow's milk (group A) or rice (group B) fermented with Lactobacillus paracasei CBA L74, or placebo (group C) for three months during the winter season. The main study outcome was the proportion of children who experienced at least one CID. All CIDs were diagnosed by family pediatricians. Fecal concentrations of innate (α- and β-defensins and cathelicidin LL-37) and acquired immunity biomarkers (secretory IgA) were also evaluated.

RESULTS

377 children (193 males, 51%) with a mean (SD) age of 32 (10) months completed the study: 137 in group A, 118 in group B and 122 in group C. Intention-to-treat analysis showed that the proportion of children who experienced at least one CID was lower in group A (51.8%) and B (65.9%) compared to group C (80.3%). Per-protocol analysis showed that the proportion of children presenting upper respiratory tract infections was lower in group A (48.2%) and group B (58.5%) compared with group C (70.5%). The proportion of children presenting acute gastroenteritis was also lower in group A (13.1%) and group B (19.5%) compared with group C (31.1%). A net increase of all fecal biomarkers of innate and acquired immunity was observed for groups A and B compared to group C. Moreover, there was a negative association between fecal biomarkers and the occurrence of CID.

CONCLUSION

Dietary supplementation with cow's milk or rice fermented with L. paracasei CBA L74 prevents CIDs in children attending daycare possibly by means of a stimulation of innate and acquired immunity.

Long-term outcome of chronic myeloid leukemia patients treated frontline with imatinib

For almost 10 years imatinib has been the therapeutic standard of chronic myeloid leukemia. The introduction of other tyrosine kinase inhibitors (TKIs) raised a debate on treatment optimization. The debate is still heated: some studies have protocol restrictions or limited follow-up; in other studies, some relevant data are missing. The aim of this report is to provide a comprehensive, long-term, intention-to-treat, analysis of 559 newly diagnosed, chronic-phase, patients treated frontline with imatinib. With a minimum follow-up of 66 months, 65% of patients were still on imatinib, 19% were on alternative treatment, 12% died and 4% were lost to follow-up. The prognostic value of BCR-ABL1 ratio at 3 months (⩽10% in 81% of patients) was confirmed. The prognostic value of complete cytogenetic response and major molecular response at 1 year was confirmed. The 6-year overall survival was 89%, but as 50% of deaths occurred in remission, the 6-year cumulative incidence of leukemia-related death was 5%. The long-term outcome of first-line imatinib was excellent, also because of second-line treatment with other TKIs, but all responses and outcomes were inferior in high-risk patients, suggesting that to optimize treatment results, a specific risk-adapted treatment is needed for such patients.

Analysis of extracellular superoxide dismutase and Akt in ascending aortic aneurysm with tricuspid or bicuspid aortic valve

Ascending aortic aneurysm (AsAA) is a consequence of medial degeneration (MD), deriving from apoptotic loss of smooth muscle cells (SMC) and fragmentation of elastin and collagen fibers. Alterations of extracellular matrix structure and protein composition, typical of medial degeneration, can modulate intracellular pathways. In this study we examined the relevance of extracellular superoxide dismutase (SOD3) and Akt in AsAA pathogenesis, evaluating their tissue distribution and protein levels in ascending aortic tissues from controls (n=6), patients affected by AsAA associated to tricuspid aortic valve (TAV, n=9) or bicuspid aortic valve (BAV, n=9). The results showed a significant reduction of SOD3, phospho-Akt and Akt protein levels in AsAA tissues from patients with BAV, compared to controls, whereas the differences observed between controls and patients with TAV were not significant. The decreased levels of SOD3 and Akt in BAV aortic tissues are associated with decreased Erk1/Erk2 phosphorylation and MMP-9 levels increase. The authors suggest a role of decreased SOD3 protein levels in the progression of AsAA with BAV and a link between ECM modifications of aortic media layer and impaired Erk1/Erk2 and Akt signaling in the late stages of the aortopathy associated with BAV.

Analysis of extracellular superoxide dismutase in fibroblasts from patients with systemic sclerosis

Systemic sclerosis (SSc) is a chronic disease of connective tissue characterized by vascular damage, autoantibody production and extensive fibrosis of skin, skeletal muscles, vessels and visceral organs. Fibrosis is a biological process involving inflammatory response and reactive oxygen species (ROS) accumulation leading to fibroblast activation. Extracellular superoxide dismutase (SOD3), a copper and zinc superoxide dismutase, which is expressed in selected tissues, is secreted into the extracellular space and catalyzes the dismutation of superoxide radical to hydrogen peroxide and molecular oxygen. Moreover, SOD3 is associated to inflammatory responses in some experimental models. In this paper we analysed, by RT-PCR and immunofluorescence, SOD3 expression and intracellular localization in dermal fibroblasts from both healthy donors and patients affected by diffuse form of SSc. Moreover, we determined SOD3 enzymatic activity in fibroblast culture medium with the xanthine/xanthine oxidase method. Increased expression of SOD3 mRNA was detected in systemic sclerosis fibroblasts (SScF), as compared to control healthy fibroblasts (HF), and SOD3 immunofluorescence staining displayed a characteristic pattern of secretory proteins in both HF and SScF. Superoxide dismutase assay demonstrated that SOD3 enzymatic activity in SScF culture medium is four times more than in HF culture medium. These data suggest that an alteration in SOD3 expression and activity could be associated to SSc fibrosis.

Decreased TET2 gene expression during chronic myeloid leukemia progression

Recently it has been demonstrated that ten-eleven-translocation-2 (TET2) gene alterations may represent a crucial event in the pathogenesis of various myeloid malignancies. To date, the loss of TET2 function has been solely ascribed to mutations in the gene coding region. In this study, we report a chronic myeloid leukemia (CML) case showing a TET2 single copy partial deletion associated to a t(4;6;11) rearrangement, appearing during the progression of the disease and responsible for a decreased TET2 gene expression. A putative role for TET2 haploinsufficiency in this patient's CML progression is discussed.

Flu and pneumococcal immunisations in HIV-infected children: methodological quality of current recommendations

OBJECTIVE

To assess the quality of guidelines, consensus statements and systematic reviews on flu and pneumococcal immunisations in HIV-infected children.

METHOD

The authors screened PubMed and Embase databases until the year 2009 for guidelines, consensus statements and systematic reviews on flu and pneumococcal immunisations in HIV-infected patients. The authors also explored relevant websites of agencies/institutions involved with HIV infection, immunisation or guidelines. The Appraisal of Guidelines for Research and Evaluation instrument and the checklists of the Scottish Intercollegiate Guidelines Network were used to evaluate the scientific quality of guidelines and systematic reviews.

RESULTS

Eighteen articles were identified. Only one guideline was of good overall quality. Generally the weakest domains were 'Applicability' and 'Editorial Independence.' Although of poor methodological quality, the main recommendations on flu and pneumococcus vaccinations were similar. There were minor differences in the type of pneumococcal vaccines in relation to patient's age, namely based on the settings in which recommendations were produced.

CONCLUSIONS

Although guidelines and systematic reviews on flu and pneumococcal vaccination in HIV-infected children came from authoritative institutions, their overall quality is poor, with the weakest fields being the methodological domains.

The applicability and efficacy of guidelines for the management of acute gastroenteritis in outpatient children: a field-randomized trial on primary care pediatricians

OBJECTIVE

To evaluate the applicability and efficacy of guidelines for the management of acute gastroenteritis (AGE) as used by pediatricians.

STUDY DESIGN

This was a national, open, randomized, controlled intervention trial. The intervention consisted of a 2-hour course based on the guidelines for management of AGE. Seventy-five randomly selected primary care pediatricians underwent training in AGE management (group A), and 75 pediatricians who were not specifically trained served as controls (group B). Each pediatrician enrolled 10 children age 1-36 months with acute-onset diarrhea. Outcome measures were guidelines applicability, duration of diarrhea, and difference in body weight between the first visit and 5-7 days later.

RESULTS

The baseline features of the children were similar in groups A (n = 617) and B (n = 692). A total of 404 of the 617 children in group A (65.5%) were fully treated according to the guidelines, compared with 20 of the 692 children in group B (3%). Most violations involved administration of unnecessary drugs or diets. The duration of diarrhea was shorter in group A (intention-to-treat: 83.3 vs 90.9 hours; P < .001). Weight gain was marginally, but statistically significantly, higher in the children treated according to the guidelines (per-protocol analysis: +16.5 gr vs -13.5 gr; P < .05).

CONCLUSIONS

Guidelines for AGE have good applicability and excellent efficacy. Adjunctive medical interventions are associated with a longer duration of diarrhea.

Adherence to antiretroviral therapy in children: a comparative evaluation of caregiver reports and physician judgement

Adherence to antiretroviral (ART) therapy, as reported by children caregivers, was investigated and compared with physicians' estimates of adherence. Two parallel structured questionnaires were administered to caregivers of 129 HIV-infected children and to their physicians in seven different Italian reference centers. Doses omitted in the last four days were recorded. Perfect adherence (>95% of prescribed doses taken in the last four days before interview) was reported by caregivers of 103 (79%) children. Five children (5%) omitted one dose of any ART drug in four days and were considered adherent. Low (<95 but >80% of doses) and poor (<80% of doses) adherence were reported by 15 (12%) and six (5%) caregivers, respectively. Forty-eight children (37%) were judged to be non-adherent by their physicians, including 35 children who were receiving all the prescribed doses according to caregivers. The physicians identified eight out of the 21 non-adherent children as adherent. Non-adherence estimates by physicians closely correlated with poor clinical conditions. These data indicate that adherence is a major problem but there is a clear discrepancy between caregiver reports and physician judgement. The results underline the need of close surveillance of adherence in HIV-positive children in order to evaluate the effectiveness of ART therapy.

Probiotics for treatment of acute diarrhoea in children: randomised clinical trial of five different preparations

OBJECTIVE

To compare the efficacy of five probiotic preparations recommended to parents in the treatment of acute diarrhoea in children. Design Randomised controlled clinical trial in collaboration with family paediatricians over 12 months.

SETTING

Primary care.

PARTICIPANTS

Children aged 3-36 months visiting a family paediatrician for acute diarrhoea.

INTERVENTION

Children's parents were randomly assigned to receive written instructions to purchase a specific probiotic product: oral rehydration solution (control group); Lactobacillus rhamnosus strain GG; Saccharomyces boulardii; Bacillus clausii; mix of L delbrueckii var bulgaricus, Streptococcus thermophilus, L acidophilus, and Bifidobacterium bifidum; or Enterococcus faecium SF68.

MAIN OUTCOME MEASURES

Primary outcomes were duration of diarrhoea and daily number and consistency of stools. Secondary outcomes were duration of vomiting and fever and rate of admission to hospital. Safety and tolerance were also recorded.

RESULTS

571 children were allocated to intervention. Median duration of diarrhoea was significantly shorter (P<0.001) in children who received L rhamnosus strain GG (78.5 hours) and the mix of four bacterial strains (70.0 hours) than in children who received oral rehydration solution alone (115.0 hours). One day after the first probiotic administration, the daily number of stools was significantly lower (P<0.001) in children who received L rhamnosus strain GG and in those who received the probiotic mix than in the other groups. The remaining preparations did not affect primary outcomes. Secondary outcomes were similar in all groups.

CONCLUSIONS

Not all commercially available probiotic preparations are effective in children with acute diarrhoea. Paediatricians should choose bacterial preparations based on effectiveness data.

TRIAL REGISTRATION NUMBER

Current Controlled Trials ISRCTN56067537 [controlled-trials.com].

Rotavirus and not age determines gastroenteritis severity in children: a hospital-based study

BACKGROUND

The severity of childhood gastroenteritis is generally believed to be age-related rather than aetiology-related. Rotavirus-induced gastroenteritis is more severe than gastroenteritis caused by other enteric pathogens and is also age-related. We thus addressed the question of whether the increased severity of rotavirus-induced gastroenteritis is related to age or to features intrinsic to the agent.

STUDY DESIGN

In this multicentre, hospital-based, prospective survey, we evaluated the severity of diarrhoea in rotavirus-positive and rotavirus-negative children up to 4 years of age. Severity was assessed with a score in four groups of age-matched children.

RESULTS

Rotavirus was detected in 381 of 911 children. Disease severity was evaluated in 589 cases for which clinical data were complete. The rotavirus-positive and rotavirus-negative groups differed with regards to diarrhoea duration, hospital stay, degree of dehydration and the number of episodes of vomiting. Gastroenteritis was more severe in rotavirus-positive than in rotavirus-negative children. In contrast, none of the main severity parameters differed in the four age groups, irrespective of the presence of rotavirus.

CONCLUSIONS

These data provide the evidence that aetiology and not age determines diarrhoeal severity. The demonstration that diarrhoea was more severe in rotavirus-positive children supports the need for a rotavirus vaccine and for studies that address the duration of vaccine protection.

Antiemetics for children with gastroenteritis: off-label but still on in clinical practice

Antiemetics are not included for treatment of vomiting associated with acute gastroenteritis (AGE) in children by standard guidelines. We performed a survey to determine antiemetic prescribing rates by Italian pediatricians. A structured questionnaire was distributed at a pediatric national conference. The majority of responders reported prescribing antiemetics for pediatric gastroenteritis. Although there is insufficient evidence to justify their use, the use of antiemetics is widely present among pediatricians.

Characterization of a recurrent translocation t(2;3)(p15-22;q26) occurring in acute myeloid leukaemia

Six patients with de novo acute myeloid leukemia (AML) and a t(2;3)(p15-21;q26-27) were identified among approximately 1000 cases enrolled in the GIMEMA trial. The t(2;3) was the sole anomaly in three patients, whereas in three cases monosomy 7, trisomy 15 and 22, and trisomy 14 represented additional aberrations. No cryptic chromosome deletions at 5q, 7q, 12p, and 20q were observed. One patient carried a FLT3 D835 mutation; FLT3 internal tandem duplication (ITD) was not detected in three patients tested. Characterization of the translocation breakpoints using a 3q26 BAC contig specific for the PRDM3 locus showed that the breakpoints were located 5' to EVIl as follows: within myelodysplatic syndrome (MDS) intron 1 (# 3), between MDS1 exons 2 and 3 in three patients (# 1, 2, 4) with a 170bp cryptic deletion distal to the breakpoint in one (# 2), and in a more centromeric position spanning from intron 2 to the 5' region of EVI1 (# 6, 5). A set of 2p16-21 BAC probes showed that the breakpoints on chromosome 2p were located within BCL11A in two separate regions (# 1, 4 and # 2-5), within the thyroid adenoma-associated (THADA) gene (# 6) or distal to the ZFP36L2 locus (# 3). Regulatory elements were present in proximity of these breakpoints. RACE PCR studies revealed a chimeric transcript in 1/6 patient analyzed, but no fusion protein. Quantitative PCR showed a 21-58-fold over-expression of the EVIl gene in all cases analyzed. The patients showed dysplasia of at least two myeloid cell lineages in all cases; they had a low-to-normal platelet count and displayed an immature CD34+ CD117+ immunophenotype. Despite intensive chemotherapy and a median age of 43 years (range 36-59), only two patients attained a short-lived response; one patient is alive with active disease at 12 months, five died at 4-14 months. We arrived at the following conclusions: (a) the t(2;3) is a recurrent translocation having an approximate 0.5% incidence in adult AML; (b) breakpoints involve the 5' region of EVIl at 3q26, and the BCL11A, the THADA gene or other regions at 2p16.1-21; (c) cryptic deletions distal to the 3q26 breakpoint may occur in some cases; (d) the juxtaposition of the 5' region of EVIl with regulatory elements normally located on chromosome 2 brings about EVI1 overexpression; (e) clinical outcome in these cases is severe.

Guanylin and E. coli heat-stable enterotoxin induce chloride secretion through direct interaction with basolateral compartment of rat and human colonic cells

We previously detected specific binding activity of Escherichia coli heat-stable enterotoxin (ST), the guanylin exogenous ligand, in rat colonic basolateral membranes. Because guanylin circulates in the bloodstream, we tested the hypothesis that it modulates intestinal ion transport by acting on the serosal side of intestinal cells. The effects of the mucosal and serosal addition of ST and guanylin on ion transport were investigated in the rat proximal colon and in Caco-2 cells in Ussing chambers, by monitoring short-circuit current (Isc). cGMP concentration was measured in Caco-2 cells by RIA. Mucosal ST addition induced an increase in Isc in rat proximal colon consistent with anion secretion. Serosal addition induced the same effects but to a lesser extent. The electrical effects observed in Caco-2 cells paralleled those observed in rat proximal colon. A pattern similar to the electrical response was observed with cGMP concentration. Guanylin addition to either side of Caco-2 cells induced the same effects as ST, although to a lesser extent. In all conditions, the electrical effect disappeared in the absence of chloride. ST directly interacts with basolateral receptors in the large intestine inducing chloride secretion through an increase of cGMP. However, the serosal effects are less pronounced compared with those observed with mucosal addition. Guanylin shows the same pattern, suggesting that it plays a role in the regulation of ion transport in the colon, but the relative importance of serosally mediated secretion remains to be determined.

Shear softening and structure in a simulated three-dimensional binary glass

Three-dimensional model binary glasses produced by quenching from a range of liquid temperatures were tested in shear over a range of strain rates using molecular-dynamics techniques. Tests were performed under constant volume and constant pressure constraints. The simulations revealed a systematic change in short-range order as a function of the thermal and strain history of the glass. While subtle signs of differences in short-range order were evident in the pair distribution function, three-body correlations were observed to be markedly more sensitive to the changes in structure. One particular structural parameter, the number of aligned three-atom clusters, was analyzed as a function of the degree of supercooling, the strain and the strain rate. The glasses quenched from the supercooled liquid regime were observed to contain an initially higher number of such clusters, and this number decreased under shear. Those quenched from high-temperature equilibrium liquids contained lower numbers of such clusters and these increased or remained constant under shear. The glasses quenched from the supercooled liquid regime showed higher strength, more marked shear softening, and an increased propensity toward shear localization. The evolution of this structural parameter depended both on its initial value and on the imposed shear rate. These results were observed to hold for simulations performed under both constant density and constant pressure boundary conditions.

Pericentric chromosome 8 inversion associated with the 5?RUNX1/3?CBFA2T1 gene in acute myeloid leukemia cases

In the present paper we report pericentric chromosome 8 inversions in two (2.4%) of 82 acute myeloid leukemia (AML) cases characterized by the 5'RUNX1/3'CBFA2T1 fusion gene. Molecular cytogenetic characterization was achieved using appropriate bacterial artificial chromosome (BAC) and P1 artificial chromosome (PAC) probes in fluorescence in situ hybridization (FISH) experiments. In these two cases the fusion gene was detected on the der(8) short arm, resulting from a pericentric chromosome 8 inversion followed by a t(8;21) rearrangement. These results suggest that heterogeneous mechanisms can lead to the generation of the 5'RUNX1/3'CBFA2T1chimeric gene.

Adherence to antiretroviral therapy and its determinants in children with human immunodeficiency virus infection: a multicentre, national study

AIM

To investigate rates and determinants of adherence to antiretroviral therapy in Italian children infected with the human immunodeficiency virus (HIV).

METHODS

An observational, cross-sectional multicentre study was performed through a structured interview with the caregivers of HIV-infected children. The interview included quantitative information on adherence in the 4 d before interview. Sociodemographic, clinical and psychosocial characteristics of children were recorded.

RESULTS

129 children (median age 96 mo) were enrolled, of whom 94 were on highly active antiretroviral therapy (HAART). Twenty-one (16%) omitted more than 5% of total doses in 4 d and were considered non-adherent. However, only 11% of caregivers reported that therapy had been administered at the correct times. No significant difference was found between age and the stage of HIV infection. Children aware of their HIV status were less adherent. Individual drugs showed a broad adherence pattern and children who received HAART were more adherent. Children receiving therapy from foster parents were more adherent than those receiving drugs from biological parents or relatives.

CONCLUSIONS

Adherence is a major problem in children. Psychological rather than clinical or sociodemographic features and types of drug are major determinants of adherence.

A novel chromosomal translocation t(3;7)(q26;q21) in myeloid leukemia resulting in overexpression of EVI1

The EVI1 proto-oncogene encodes a nuclear zinc finger protein that acts as a transcription repressor factor. In myeloid leukemia it is often activated by chromosomal rearrangements involving band 3q26, where the gene has been mapped. Here we report two leukemia cases [a chronic myeloid leukemia blast crisis (CML-BC) and an acute myeloid leukemia (AML) M4] showing a t(3;7)(q26;q21) translocation in a balanced and unbalanced form, respectively. Fluorescent in situ hybridization (FISH) analysis revealed that both patients showed a breakpoint on chromosome 3 inside the clone RP11-33A1 containing the EVI1 oncogene and, on chromosome 7, inside the clone RP11-322M5, partially containing the CDK6 oncogene which is a D cyclin-dependent kinase gene, observed to be overexpressed and disrupted in many hematological malignancies. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis showed overexpression of EVI1 in both cases, but excluded the presence of any CDK6/ EVI1 fusion transcript. CDK6 expression was also detected. Together, these data indicate that EVI1 activation is likely due not to the generation of a novel fusion gene with CDK6 but to a position effect dysregulating its transcriptional pattern.

Short duration of breastfeeding and early introduction of cow's milk as a result of mothers' low level of education

Inappropriate infant feeding including a lack of breastfeeding and the early introduction of cow's milk are the most common forms of infant feeding malpractice. To evaluate the hypothesis that infant feeding malpractices are associated with mothers' low level of education, questionnaires were administered to 400 mothers of infants below 12 mo of age divided into 3 groups according to their various educational levels. Items included the type of milk given at birth and at 1, 3 and 6 mo of age. To investigate the efficacy of paediatricians in orienting infant feeding, the same questionnaire was given to 30 paediatricians in primary paediatric healthcare, in hospitals or in private practices. Initiation of breastfeeding was similar in the three groups. An analysis of the data showed that an increasing number of infants born to mothers of low and intermediate educational level did not receive exclusive breastfeeding compared with those with a higher level of education, a difference that was significant as early as 1 mo of age. In infants aged 3 mo, the prevalence of exclusive breastfeeding was 37%, 40% and 65% in the three groups, respectively, in relation to progressively increasing levels of education. In infants of 6 mo, the respective prevalence rates were 13%, 15% and 48%. Early introduction of cow's milk showed a similar correlation with educational level. A greater number of infants born to mothers with a low level of education received cow's milk at 3 mo of age compared with those born to mothers with an intermediate education (12% vs 5%). A similar difference was observed between the latter group and infants born to mothers with a high educational level (0%). This pattern was supported by data for infants at 6 mo of age with prevalence rates for cow's milk feeding of 39%, 20% and 0% in the three groups in association with progressively increasing level of educational (p < 0.05). The analysis of the paediatricians' response to the questionnaire showed that while physicians know and correctly prescribe age-related infant nutrition regimens, they are unaware that a substantial number of mothers do not comply with what they prescribe. Overall, these data support the relationship between a low educational level and infant feeding malpractice and suggest that a more effective role should be played by paediatricians in supporting an adequate duration of breastfeeding and the use of formula rather than cow's milk protein.

Deletions on der(9) chromosome in adult Ph-positive acute lymphoblastic leukemia occur with a frequency similar to that observed in chronic myeloid leukemia

The t(9;22)(q34;q11), generating the Philadelphia chromosome (Ph), is found in more than 90% of patients with chronic myeloid leukemia (CML) and in 15-30% of adults with acute lymphoblastic leukemia (ALL). Different groups have recently described the presence of large genomic deletions adjacent to the translocation breakpoint on the derivative chromosome 9 in 9-16% of CML patients. In the present paper, we report a FISH study of 45 Ph+ adult ALL patients with the aim of investigating the presence of deletions on derivative chromosome 9. In four (9%) of 45 cases, all showing an M-bcr, we detected deletions on der(9). The frequency of deletions we observed is similar to that reported in CML patients. The association of an M-bcr breakpoint and deletions appears significant (P=0.03). Some authors have suggested a very low incidence of der(9) deletions in ALL. This discrepancy can be explained by taking into account the low percentage of M-bcr ALL patients in the latter study (18%) compared to the present one (44%).

Effects of HIV-1 Tat protein on ion secretion and on cell proliferation in human intestinal epithelial cells

BACKGROUND & AIMS

Severe diarrhea and enteropathy of unknown origin are frequent in patients infected with human immunodeficiency type 1 virus (HIV-1). The HIV-1 transactivating factor protein (Tat) is a key factor in the pathogenesis of acquired immunodeficiency syndrome. We investigated whether Tat could directly induce ion secretion and cell damage in enterocytes.

METHODS

Electrical parameters (ion transport studies) were measured in Caco-2 cell monolayers and in human colonic mucosa specimens mounted in Ussing chambers. The effect of Tat on intestinal mucosa integrity was determined by monitoring the transepithelial electrical resistance of Caco-2 cell monolayers. (3)H-thymidine incorporation and cell count were used to evaluate the effect of Tat on cell growth. Intracellular calcium concentrations were measured at the single-cell level using microfluorometry technique.

RESULTS

Tat protein induced ion secretion in Caco-2 cells and in human colonic mucosa similar to that induced by bacterial enterotoxins. It also significantly prevented enterocyte proliferation. In both instances, the effect of Tat was maximum at concentrations within the range detected in the sera of HIV-1-infected patients. Anti-Tat antibodies inhibited both effects. Ion secretion and the antiproliferative effects were mediated by L-type Ca(2+) channels. An increase in intracellular calcium concentration in Caco-2 cells was found after addition of Tat.

CONCLUSIONS

These results indicate that Tat may be involved in HIV-1-related intestinal disease through direct interaction with enterocytes.

Extramedullary involvement at relapse in acute promyelocytic leukemia patients treated or not with all-trans retinoic acid: a report by the Gruppo Italiano Malattie Ematologiche dell'Adulto

PURPOSE

Recent reports of extramedullary disease (EMD) at recurrence in acute promyelocytic leukemia (APL) have raised increasing concern about a possible role of retinoic acid (RA) therapy.

PATIENTS AND METHODS

We analyzed the risk of developing EMD localization at relapse in APL patients enrolled onto two consecutive studies of the Gruppo Italiano Malattie Ematologiche dell'Adulto. The studies investigated chemotherapy alone (LAP0389) versus RA plus chemotherapy (AIDA).

RESULTS

When all relapse types were taken into account, 94 (51%) of 184 patients and 131 (18%) of 740 patients who attained hematologic remission underwent relapse in the LAP0389 and AIDA studies, respectively (P < .0001). EMD localization was documented in five (5%) of 94 and 16 (12%) of 131 patients (P = .08). Hematologic and/or molecular relapse was diagnosed concomitantly in all but two patients with EMD in the AIDA study. For patients in the LAP0389 and AIDA series, the probability of EMD localization of any type at relapse was 3% and 4.5%, respectively (P = .79), while the probability of CNS involvement was 0.6% and 2% (P = .28). No significant differences were found with regard to mean WBC count and promyelocytic leukemia/retinoic acid receptor-alpha junction type in comparisons of patients with EMD and hematologic relapse.

CONCLUSION

APL patients receiving all-trans retinoic acid in addition to chemotherapy have no increased risk of developing EMD at relapse as compared with those treated with chemotherapy alone.

Retinal abnormalities in newly diagnosed adult acute myeloid leukemia

Retinal abnormalities (RA) are very frequently observed in adult patients with acute myeloid leukemia (AML), but the clinical significance of these findings has not been fully investigated. We examined the fundus oculi in a cohort of 122 adult patients with AML at presentation and analyzed some clinical and biological features to assess whether there was any association with RA. For this purpose, we subdivided the patients into two groups according to the presence or absence of RA (groups 1 and 2, respectively). We considered current laboratory parameters such as white blood cell (WBC) count, hemoglobin (Hb), platelets and serum lactate dehydrogenase (LDH). Moreover, we subdivided the patients into two groups according to age <60 (group A) or > or =60 years (group B) to evaluate a possible association between RA and response to treatment and/or overall survival (OS). In our series, a higher median age and a lower Hb value were associated with group 1 (p = 0.001 and p = 0.04, respectively); the median LDH value was 812 U/l (range 224-5,551) and 607 (range 181-5,244) for groups 1 and 2, respectively (p = 0.02). There was no association between RA and karyotypic alterations. In terms of outcome, in group A (<60 years), 80% patients who achieved complete remission (CR) were in group 2 vs. 13% nonresponders (NR) (p < 0.0001). Median OS of group 2 patients was 49.7 months compared with 7.2 months for those in group 1 (p = 0.002). In group B, 58% patients who achieved CR were in group 1 vs. 15% NR (p < 0.006). Median OS of patients in group 2 was 14.6 months compared with 2.9 months in group 1 (p = 0.02). Our data show that RA are significantly associated with some biological features and with shorter OS in AML patients and this parameter seems to be an effective clinical sign of poor prognosis in terms of CR.

Colonocyte basolateral membranes contain Escherichia coli heat-stable enterotoxin receptors

Heat-stable enterotoxin (ST(a)) elaborated by E. coli is a major cause of diarrhea. The transmembrane protein guanylyl cyclase C (GC-C) is the acknowledged receptor for ST(a) and for the mammalian peptides guanylin and uroguanylin. Binding to GC-C results in generation of cGMP, activation of type II cGMP-dependent protein kinase, phosphorylation of CFTR and increased chloride and bicarbonate secretion. We had previously shown that ST(a) receptors (GC-C) are found on the brush border membranes of small intestinal enterocytes and of colonocytes. However, since it has subsequently been shown that the endogenous ligands for these receptors, guanylin and uroguanylin, circulate in blood, we proposed the existence of ST(a) binding sites on the basolateral membranes (BLM) of colonocytes. Specific binding of 125I-ST(a) to rat colonocyte BLM was seen. The kinetics of binding to the BLM were similar to binding to BBM. The nature of the BLM receptor is unknown. This suggests that circulating guanylin and uroguanylin, analogues of ST(a), may also function via the basolateral surface.

Biochemical behaviour of norbixin during in vitro DNA damage induced by reactive oxygen species

Naturally occurring antioxidants such as carotenoids are extensively studied for their potential in reducing the risk for cancer and other chronic diseases. In the present study, the radical-scavenger activity of the food additive norbixin, a water-soluble carotenoid extracted from Bixa orellana seeds and commercialized as annatto, was evaluated under conditions of DNA damage induced by reactive oxygen species, particularly by hydroxyl radicals. The cell-free scavenger activity of norbixin was evaluated using plasmid DNA as target molecule and Sn2+ or Fe2+ as oxidant. The addition of H2O2 enhanced DNA breakage induced by metal ions, particularly Fe2+. Under these conditions, norbixin started to protect plasmid DNA against single- and double-strand breakage at a metal:norbixin ratio of 1:1 (Sn2+) and 1:10 (Fe2+). However, at lower ratios to Sn2+, norbixin enhanced Sn2+-induced DNA breakage (P < 0.05). The ability of norbixin to protect genomic DNA against oxidative damage was assessed in murine fibroblasts submitted to H2O2-induced oxidative stress and the results were evaluated by the comet assay. Under low serum conditions (2 % fetal bovine serum (FBS)), a protective effect of norbixin against H2O2-induced DNA breakage was inversely related to its concentration, a protection ranging from 41 % (10 microm) to 21 % (50 microm). At higher concentrations of norbixin, however, oxidative DNA breakage was still enhanced, even in the presence of a high serum concentration (10 % FBS). Under normal conditions, norbixin per se has no detectable genotoxic or cytotoxic effects on murine fibroblasts. The antimutagenic potential of norbixin against oxidative mutagens was also evaluated by the Salmonella typhimurium assay, with a maximum inhibition of 87 % against the mutagenicity induced by H2O2. Although plasmid DNA and Ames data indicated that norbixin can protect DNA against oxidative damage, it seems to be a risky guardian of genomic DNA as it can also increase the extent of oxidative damage.

The effect of electromagnetic field exposure on the formation of DNA lesions

In an attempt to determine whether electromagnetic field (EMF) exposure might lead to DNA damage, we exposed SnCl2-treated pBR322 plasmids to EMF and analysed the resulting conformational changes using agarose gel electrophoresis. An EMF-dependent potentiation of DNA scission (i.e. the appearance of relaxed plasmids) was observed. In confirmation of this, plasmids pre-exposed to EMF also were less capable of transforming Escherichia coli. The results indicate that EMF, in the presence of a transition metal, is capable of causing DNA damage. These observations support the idea that EMF, probably through secondary generation of reactive oxygen species, can be clastogenic and provide a possible explanation for the observed correlation between EMF exposure and the frequency of certain types of cancers in humans.