In vitro cellular characteristics and survival responses of human astrocytoma clones to chloroethyl-nitrosoureas and dianhydrogalactitol

Three permanent clones were derived from a single astrocytoma cell line and were characterized for in vitro cell kinetics, chromosomal properties and for their responses to the anticancer drugs: 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU); 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU); 1-(2-chloroethyl)-3-(2,6-dioxo-3-piperidyl-1-nitrosourea) (PCNU); and 1,2:5,6-dianhydrogalactitol (GAL); all of which have been shown to cross the blood brain barrier. The clones showed different population doubling times, saturation densities, plating efficiencies, chromosome counts, ploidy, cell cycle phase distributions and DNA indices. The only positive correlation among these parameters was between the population doubling times and the modal chromosome numbers; the lower the chromosome number, the shorter the doubling time. No correlation was observable between any of the cellular properties and responses to the four drugs. The clones showed a differential sensitivity to the nitrosoureas, seen maximally as a 600-fold difference in survival between two of the clones treated with the same dose of BCNU. In contrast, the clones exhibited almost identical and uniform sensitivities to galactitol, suggesting that this agent exerted its cytotoxic effects by similar mechanisms in each of the clones. By comparison BCNU (at the tested doses and duration of drug exposure used in this study) was found to be the most effective of the agents tested.     

ACE inhibitors and angiotensin II receptor blockers in IgA nephropathy with mild proteinuria: the ACEARB study

Few studies have investigated IgA nephropathy patients presenting with 'favorable' clinical features at onset, such as normal renal function, proteinuria<1 g/24 hours and the absence of hypertension, and no controlled clinical trials have tested the effects of treatment in such patients who may nevertheless develop end-stage renal disease. It is therefore important to find a well-tolerated and economic therapy capable of decreasing their risk of high proteinuria and blood pressure levels. The aim of this multicenter open-label randomized clinical trial is to test whether blocking the renin-angiotensin system (RAS) decreases the risk of progression in patients aged 3-60 years with biopsy-proven benign IgA glomerulonephritis, proteinuria levels of 0.3-0.9 g/24 hours, and normal renal function and blood pressure. The RAS is blocked by first using a single drug class (angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker), and then combining the 2 classes as soon as the 1-drug blockade has become ineffective. We plan to enroll 378 patients over the next 3 years and randomize them to receive ramipril 5 mg/day (3 mg/m2 in children) (group A), irbesartan 300 mg/day (175 mg/m 2 in children) (group B) or supportive therapy (group C); if an increase in proteinuria of at least 50% from baseline is detected after 6 months of treatment, the other RAS inhibitor will be added. The observation period will be at least 5 years (except in the case of the development of the primary end point).     

Role of NK-1 and NK-2 tachykinin receptor antagonism on the growth of human breast carcinoma cell line MDA-MB-231

We demonstrate that neurokinin A (NKA) and substance P (SP) play a role in the proliferation of the estrogen receptor-negative (ER-) cell line MDA-MB-231, a human breast carcinoma expressing both NK-1 and NK-2 receptors. In vitro experiments showed that the specific receptor antagonists MEN 11,467 (NK-1) and nepadutant (MEN 11,420; NK-2) inhibited tumor cell proliferation, and blocked the stimulatory effect of SP and NKA. Anti-tumoral activity of NK-1 and NK-2 receptor antagonists was demonstrated in nude mice, measuring growth inhibition of MDA-MB-231 tumor cells xenografted s.c. and by using the hollow-fiber assay. In both systems a significant inhibition was found when compounds were administered at 5 mg/kg i.v. every day for 2 weeks. Results obtained from both these models suggest that the in vivo activity of NK-1 and NK-2 antagonists may be a result of a cytostatic effect rather than a cytotoxic effect. Our results suggest that the control of breast carcinoma (ER-) growth by tachykinin receptor antagonists may become a new form of targeted therapy for these human tumors.     

Association of endodontic infection with detection of an initial lesion to the cardiovascular system

Introduction

Dental infections might predispose toward the onset of cardiovascular disease (CVD). To date, only a few studies, yielding inconclusive findings, have investigated the potential correlation between apical periodontitis (AP) and CVD. The aim of this study (as the first part of a prospective study) was to evaluate, in the absence of CV risk factors, whether subjects with AP were more exposed to the pathogenetic indices of an atherosclerotic lesion.

Methods

Forty men between the ages of 20 and 40 years who were free from periodontal disease, CVD, and traditional CV risk factors were enrolled in the study; 20 subjects had AP, and 20 acted as controls. All subjects underwent dental examination and complete cardiac assessment: physical examination, electrocardiogram, conventional and tissue Doppler echocardiography, and measurement of endothelial flow reserve (EFR). The following laboratory parameters were tested: interleukins -1, -2, and -6 (IL-1, IL-2, IL-6), tumor necrosis factor alpha, and asymmetrical dimethylarginine (ADMA). Data were analyzed by using the 2-tailed Student's t test, Pearson t test (or Spearman t test for nonparametric variables), and multivariate linear regression analysis.

Results

Echocardiography revealed no abnormalities in any of the subjects studied. ADMA levels were inversely correlated with EFR (P < .05) and directly correlated with IL-2 (P < .001). Patients with AP presented with significantly greater blood concentrations of IL-1 (P < .05), IL-2 (P < .01), IL-6 (P < .05), and ADMA (P < .05) and a significant reduction of EFR (P < .05).

Conclusions

Increased ADMA levels and their relationship with poor EFR and increased IL-2 might suggest the existence of an early endothelial dysfunction in young adults with AP.     

Ex vivo gene therapy with lentiviral vectors rescues adenosine deaminase (ADA)-deficient mice and corrects their immune and metabolic defects

Adenosine deaminase (ADA) deficiency is caused by a purine metabolic dysfunction, leading to severe combined immunodeficiency (SCID) and multiple organ damage. To investigate the efficacy of ex vivo gene therapy with self-inactivating lentiviral vectors (LVs) in correcting this complex phenotype, we used an ADA(-/-) mouse model characterized by early postnatal lethality. LV-mediated ADA gene transfer into bone marrow cells combined with low-dose irradiation rescued mice from lethality and restored their growth, as did transplantation of wild-type bone marrow. Mixed chimerism with multilineage engraftment of transduced cells was detected in the long term in animals that underwent transplantation. ADA activity was normalized in lymphocytes and partially corrected in red blood cells (RBCs), resulting in full metabolic detoxification and prevention of severe pulmonary insufficiency. Moreover, gene therapy restored normal lymphoid differentiation and immune functions, including antigen-specific antibody production. Similar degrees of detoxification and immune reconstitution were obtained in mice treated early after birth or after 1 month of enzyme-replacement therapy, mimicking 2 potential applications for ADA-SCID. Overall, this study demonstrates the efficacy of LV gene transfer in correcting both the immunological and metabolic phenotypes of ADA-SCID and supports the future clinical use of this approach.     

Thrombocytopenia-absent-radius syndrome in a child showing a larger 1q21.1 deletion than the one in his healthy mother, and a significant downregulation of the commonly deleted genes

Thrombocytopenia-absent-radius (TAR) syndrome is a rare condition characterized by thrombocytopenia and bilateral absence of the radii with presence of both thumbs. The phenotype has a variable expression. A 200 kb minimal deletion at 1q21.1 is present in all patients. However, the microdeletion, ranging up to 1100 kb in length, is not sufficient to cause the disease. Indeed it is present in 75-80% of unaffected parents. It is assumed that the phenotype develops only in the presence of one or more additional, as-yet-unknown, deletion modifiers (mTARs). We report here on a child affected by TAR syndrome associated with Langerhans cell histiocytosis. Unexpectedly, he showed a 2.029 kb deletion at 1q21.1, almost twice that of the unaffected mother (957 kb). Interestingly, the mother-to-son increased size of the deleted region was already observed in two cases of constitutional diseases, although both resulting as chromosomal terminal deletions. Noteworthy, qPCR experiments, never before performed for patients with TAR syndrome, disclosed that the proband had a statistically significant downregulation of the majority of the genes mapping inside the part of the deletion shared with the mother. The mother, on the contrary, did not show the same downregulation. In summary, the present report adds new insights on the pathogenesis of TAR syndrome, that may represent fruitful directions for future research.     

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.