The size of adrenal incidentalomas correlates with insulin resistance. Is there a cause‐effect relationship?

Context Adrenal incidentalomas (AI) have often been associated with a high prevalence of insulin resistance (IR) and cardiovascular risk factors, although direct measurement of insulin sensitivity (IS) has never been carried out. Objective We aimed to investigate whether the morphological and hormonal features of AI correlate with the presence and severity of IR, using the hyperinsulinaemic euglycaemic clamp (HEC). Design and Measurements Forty patients with AI (22 women) with a mean age of 58·5 ± 11·1 years underwent hormonal and morphological evaluation. Nineteen patients with AI without known history of diabetes mellitus (DM) or impaired glucose tolerance (IGT) and 17 matched controls underwent oral glucose tolerance test (OGTT) and hyperinsulinaemic euglycaemic clamp (HEC). Results Diabetes mellitus was observed in 13 patients (33%), while three (8%) had IGT. Thirty‐one of the AI were nonfunctioning (82·5%), whereas two (5%) secreted cortisol (Cushing’s syndrome) and seven (12·5%) showed subclinical secretion of cortisol. The 19 patients with nonfunctioning AI were more insulin resistant than controls (glucose up‐take: 4·58 ± 1·80 vs 5·85 ± 2·48 mg/kg/min respectively; P = 0·01); IS was inversely related to the mass size (r = ?0·57; P = 0·04), free urinary cortisol (r = ?0·68; P = 0·01), serum cortisol after 1‐mg dexamethasone suppression (?0·65; P = 0·02) and percentage of trunk fat mass (?0·77; P = 0·02) and directly related to serum adreno cortico tropic hormone (ACTH) (r = 0·62; P = 0·03). After performing multivariate regression, the mass size was found to be the most powerful predictor of IR. Conclusion Our study showed a high prevalence of insulin resistance in patients with nonfunctioning AI and suggests its possible involvement in AI growth.     

An open-label, pilot study of fludarabine, cyclophosphamide, and alemtuzumab in relapsed/refractory patients with B-cell chronic lymphocytic leukemia

Although combination regimens have improved outcomes over monotherapy in chronic lymphocytic leukemia (CLL), patients eventually relapse. Combined fludarabine, cyclophosphamide, and monoclonal anti-CD52 antibody alemtuzumab (FCC) provided synergistic cytotoxicity with effective clearing of minimal residual disease. This phase 2 study determined FCC efficacy and safety in relapsed/refractory CD52(+) B-CLL after ≥ 1 line of treatment. From January 2005 through June 2008, up to 6 courses of oral fludarabine 40 mg/m2 per day, oral cyclophosphamide 250 mg/m2 per day, and subcutaneous alemtuzumab (Mab-Campath) 10 mg (increased to 20 mg after first 10-patient cohort) were administered days 1 to 3 every 28 days. The primary objective was overall response rate (ORR); secondary objectives included response duration, time to disease progression, and safety and tolerability. ORR was 67% in 43 patients; 30% achieved complete response. ORR significantly improved with 1 versus ≥ 2 prior therapies (P = .018), and without versus with previous monoclonal antibody treatment (P = .003). Median progression-free survival was 24.4 months, not reached in patients achieving complete response. Median overall survival was 33.6 months. Myelosuppression was the most common adverse event, with a low percentage of cytomegalovirus reactivations and manageable infections. However, close vigilance of opportunistic infections is warranted. FCC provides effective immunotherapy in relapsed/refractory CLL, including in patients with poor-risk prognostic factors.     

GH, but not GHRH, plays a role in the development of experimental autoimmune encephalomyelitis

GH has been suggested to influence the function of the immune system in several species. Experimental autoimmune encephalomyelitis (EAE) (an animal model for multiple sclerosis) has been reported not to occur in GH-deficient (GHD) mice. The aim of this study was to elucidate the effects of GH and GHRH replacement on development of EAE in a mouse model of isolated GHD due to removal of the GHRH gene [GHRH knockout (GHRHKO)]. We studied two groups of adult female mice: 12 GH-sufficient animals (control) and 36 GHRHKO animals. All mice were immunized with myelin oligodendrocyte glycoprotein peptide, a peptide known to induce EAE. GHRHKO mice were left untreated or were treated for 4 wk with daily sc injections of recombinant GH or of a GHRH super agonist JI-38 (JI38-GHD). Evaluation of EAE symptoms was carried out daily, and T-proliferative assay and histopathological analysis of the spinal cord were performed. GHRHKO mice were less prone to develop EAE when compared with control mice. GH (but not JI-38) restored the original susceptibility of mice to the disease, despite lack of complete serum IGF-I normalization. GH treatment was also associated with a markedly increase in spleen size and T-cell proliferation specific to myelin oligodendrocyte glycoprotein peptide. GH (but not GHRH) plays an important role in the development of EAE.     

Imatinib induces hematologic and cytogenetic responses in patients with chronic myelogenous leukemia in myeloid blast crisis: results of a phase II study

Blast crisis is the most advanced stage of chronic myelogenous leukemia (CML) and is highly refractory to therapy. CML is caused by expression of the chimeric BCR-ABL tyrosine kinase oncogene, the product of the t(9;22) Philadelphia translocation. Imatinib (Glivec, formerly STI571) is a rationally developed, orally administered inhibitor of the Bcr-Abl tyrosine kinase. A total of 260 patients with CML were enrolled in a phase II trial, of whom 229 had a confirmed diagnosis of CML in blast crisis. Patients were treated with imatinib in daily oral doses of 400 mg or 600 mg. Imatinib induced hematologic responses in 52% of patients and sustained hematologic responses lasting at least 4 weeks in 31% of patients, including complete hematologic responses in 8%. For patients with a sustained response, the estimated median response duration was 10 months. Imatinib induced major cytogenetic responses in 16% of patients, with 7% of the responses being complete. Median survival time was 6.9 months. Nonhematologic adverse reactions were frequent but generally mild or moderate. Episodes of severe cytopenia were also frequent and were attributable to the underlying condition and treatment with imatinib. Drug-related adverse events led to discontinuation of therapy in 5% of patients, most often because of cytopenia, skin disorders, or gastrointestinal reactions. These results demonstrate that imatinib has substantial activity and a favorable safety profile when used as a single agent in patients with CML in blast crisis. Additional clinical studies are warranted to explore the efficacy and feasibility of imatinib used in combination with other antileukemic drugs.     

Conformation of peptides bound to the transporter associated with antigen processing (TAP)

The ATP-binding cassette transporter associated with antigen processing (TAP) plays a key role in the adaptive immune defense against infected or malignantly transformed cells by translocating proteasomal degradation products into the lumen of the endoplasmic reticulum for loading onto MHC class I molecules. The broad substrate spectrum of TAP, rendering peptides from 8 to 40 residues, including even branched or modified molecules, suggests an unforeseen structural flexibility of the substrate-binding pocket. Here we used EPR spectroscopy to reveal conformational details of the bound peptides. Side-chain dynamics and environmental polarity were derived from covalently attached 2,2,5,5-tetramethylpyrrolidine-1-oxyl spin probes, whereas 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid spin-labeled peptides were used to detect backbone properties. Dependent on the spin probe's position, striking differences in affinity, dynamics, and polarity were found. The side-chains' mobility was strongly restricted at the ends of the peptide, whereas the central region was flexible, suggesting a central peptide bulge. In the end, double electron electron resonance allowed the determination of intrapeptide distances in doubly labeled peptides bound to TAP. Simulations based on a rotamer library led to the conclusion that peptides bind to TAP in an extended kinked structure, analogous to those bound to MHC class I proteins.     

Vascular effects of wine polyphenols

Moderate consumption of red wine has been putatively associated with lowering the risk of developing coronary heart disease. This beneficial effect is mainly attributed to the occurrence of polyphenol compounds such as anthocyanosides (ACs), catechins, proanthocyanidins (PAs), stilbenes and other phenolics in red wine. This review focuses on the vascular effects of red wine polyphenols (RWPs), with emphasis on anthocyanosides and proanthocyanidins. From in vitro studies, the effect of red wine polyphenols on the vascular tone is thought to be due to short- and long-term mechanisms. NO-mediated vasorelaxation represents the short-term response to wine polyphenols, which exert the effect by increasing the influx of extracellular Ca(2+), and the mobilization of intracellular Ca(2+) in endothelial cells. Polyphenolic compounds may also have long-term properties, as they increase endothelial NO synthase expression acting on the promoter activity. In addition, they decrease the expression of adhesion molecules and growth factors, involved in migration and proliferation of vascular smooth muscle cells. Moreover, they inhibit platelet aggregation. However, a paucity of data as regards the bioavailability and metabolism of these compounds in human studies is a limiting factor to proving their efficacy in vivo.     

ABCB4 and ABCB11 mutations in intrahepatic cholestasis of pregnancy in an Italian population

BackgroundGenetic alterations in the ATP-binding cassette subfamily B member 4 (ABCB4) and ATP-binding cassette subfamily B member 11 (ABCB11) have been associated to the onset of intrahepatic cholestasis of pregnancy (ICP) in predisposed women.AimsTo identify new and/or frequent ABCB4 and ABCB11 genes variants in a cohort of Italian patients with ICP and to evaluate the possible pathogenetic role for the novel mutations identified.MethodsDNA of 33 unrelated Italian women with obstetric cholestasis were screened for mutations in the entire coding sequence of ABCB4 and ABCB11 genes. Polymerase chain reaction and automated sequencing was performed on the 27 coding exons of both genes.ResultsGenotyping revealed 11 mutations, 5 of whom were novel variants: 2 localized on ABCB4 (p.I587DfsX603, p.I738LfsX744) and 3 on ABCB11 (p.V284D, p.Q558H, p.P731S). The most severe phenotypes were associated with the variants p.I587DfsX603, p.I738LfsX744 and p.V284D. Moreover, the already described mutation p.N510S found in ABCB4 seems to be strictly involved in the onset of ICP in that particular patient.ConclusionsOur data support the hypothesis of a significant involvement of ABCB4 mutations in the onset of ICP, but also confirm an important role for ABCB11 mutations in increasing the susceptibility to cholestasis of pregnancy.     

Changes of liver fat content and transaminases in obese children after 12-mo nutritional intervention

AIM: To assess a relationship between longitudinal changes in liver fat content and biochemical parameters in obese children after 1-year nutritional intervention.METHODS: Forty-six obese children, 21 males and 25 females, aged 6-14 years, underwent metabolic measurements, liver ultrasonography (US) and chemical-shift magnetic resonance imaging (MRI) examinations at baseline and after 1-year nutritional intervention. A child was defined obese if her/his body mass index (BMI) was above the age- and sex-adjusted BMI Cole’s curve passing through the cut-off of 30 kg/m² at 18 years. BMI Z scores were calculated and adjusted for age and gender by using the Cole’s LMS-method and Italian reference data. Biochemistry included serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Abdominal US and chemical-shift MRI were performed according to a randomized sequence. The same radiologist performed US by a GE Logiq 9 (General Electric Healthcare Medical Systems, Milwaukee, WI, United States) using a 3.5-MHz convex array transducer. Liver echogenicity was evaluated independently on videotape by 3 radiologists unaware of the child and MRI outcomes, and a consensus was established. Another experienced radiologist, unaware of the child and US data, performed the abdominal chemical-shift MRI with a 1-t system NT-Intera (Philips Medical Systems, Best, The Netherlands) and a phased-array coil. Liver fat fraction (FF) on MRI was judged elevated when greater than 9%. A FF > 18% was considered expressing more severe cases of fatty liver according to Fishbein. A nutritional-behavioral intervention was recommended to promote a normocaloric balanced diet and active lifestyle based on the Italian guidelines for treatment of childhood obesity.RESULTS: Compared to baseline, at the end of intervention children showed lower intakes of energy (mean ± SD: 2549 ± 1238 Kcal vs 1770 ± 622 Kcal, P < 0.0001), total fat (90 ± 47 g vs 52 ± 23 g, P < 0.0001), carbohydrates (356 ± 174 g vs 241 ± 111 g, P = 0.001), and protein (99 ± 48 g vs 75 ± 23 g, P = 0.006) intakes. Prevalence of FF ≥ 9% declined from 34.8% to 8.7% (P < 0.01), with a mean reduction of 7.8% (95%CI: 5.0-10.6). At baseline, FF was associated with liver biochemical parameters (maximum P < 0.001). At the end of the intervention association was found with AST (P = 0.017). Change of FF was associated with change in AST (P = 0.027) and ALT (P = 0.024). Rate of increased liver echogenicity declined from 45.6% to 21.7% (P < 0.0001). Liver echogenicity was associated with ALT at baseline only (P < 0.001). An age- and sex- adjusted multiple regression analysis showed that FF change was independently associated with change in serum AST (adjusted regression coefficient 0.348, P = 0.048).CONCLUSION: The results suggest that in obese children longitudinal changes in liver fat content based on MRI may be associated with change in serum transaminases suggesting novelty in monitoring nonalcoholic fatty liver disease.     

Local immune activity in acute coronary syndrome: oxLDL abrogates LPS-tolerance in mononuclear cells isolated from culprit lesion

Background

OxLDL plays a major role in the initiation and progression of atherosclerotic lesions even though further factors are needed to promote fibrous cap rupture and thrombotic occlusion of the arterial lumen. Pathogens have been implicated in this process but it remains unclear how they can cooperate with oxLDL in amplifying the destructive inflammatory response.

Objective

To phenotypically analyze culprit coronary inflammatory cells, evaluate their responsiveness to endotoxins and ascertain whether oxLDL alters the sensitivity of coronary mononuclear cells to bacterial components.

Methods

Mononuclear cells isolated from culprit and non-culprit coronary blood samples of patients with ST-segment elevation myocardial infarction (STEMI) and controls were analyzed for cell-specific surface markers and cytokines by flow-cytometry.

Results and conclusions

CD14 + cells contained elevated levels of TLR4, expressed high CD80, and produced huge amounts of inflammatory cytokines in response to LPS. Using a well-established model of endotoxin tolerance, we next showed that mononuclear cells isolated from control coronary artery, but not from culprit coronary artery, were tolerant to LPS, but pre-treatment of such cells with oxLDL abrogated LPS tolerance. Flow-cytometry analysis also showed that IL-17A, IL-21 and IFN-γ were over-produced by CD4 + and CD56 + cells isolated from the culprit coronary artery. All this data indicate that monocytes circulating in the culprit coronary artery of patients with STEMI are primed to synthesize high levels of inflammatory cytokines and suggest that oxLDL can amplify the inflammatory response of such cells to endotoxins.     

Efficacy of an analysis of lymphocyte subsets in predicting the clinical response to α-interferon therapy in thalassaemia patients with chronic infection by hepatitis C virus: a pilot study

Summary. α-interferon (α-IFN) has been used to treat chronic non-A non-B hepatitis in thalassaemic patients with response rates from 45% to 83%. Unfortunately, treatment with α-IFN is associated with side-effects which have a negative effect on the quality of life of the patient. Therefore it would be useful if we could distinguish in advance those patients who would benefit from such therapy from those who would not. In the present study we found that the modification of lymphocyte subsets 20 h after the administration of the first dose of α-IFN revealed that relative numbers of T helper lymphocytes (CD4⁺) increased in three non-responding patients and decreased in five responding patients, whereas those of T suppressor lymphocytes (CD8⁺), and natural killer cells (CD57⁺. CD16⁺) decreased in non-responding patients and increased in responding patients. Therefore analysis of the lymphocyte subsets CD4, CD8, CD57 and CD16 before and 20 h after the administration of α-IFN can be used to predict the clinical response to treatment with α-IFN.