SPG5 and multiple sclerosis: clinical and genetic overlap?

BACKGROUND: Autosomal recessive (AR) spastic paraplegia type 5 (SPG5) is due to mutations in the CYP7B1 gene, encoding for the cytochrome P450-7B1, responsible for oxysterols 7α-hydroxylation. Oxysterol/cholestenoic acids pool plays a role in motor neuron survival and immune response. SPG5 is characterized by white matter abnormalities at brain resonance imaging (MRI). In view of clinical presentation and MRI findings, multiple sclerosis (MS) is a possible differential diagnosis of SPG5. This study aimed to evaluate the frequency of CYP7B1 mutations in patients with MS. METHODS: One hundred and seventeen MS patients with clinical spastic paraplegia or possible AR transmission were selected for the mutational screening. RESULTS: Forty-three patients had primary progressive, 26 relapsing remitting, 26 secondary progressive, and 22 relapsing progressive MS clinical course. No CYP7B1 homozygous mutations were identified. Two novel variants and one pathogenic mutation were found at heterozygous state. CONCLUSIONS: The two novel variants cosegregated with pyramidal signs and autoimmune diseases suggesting that they might be susceptibility factors. Reduced cytochrome P450-7B1 enzymatic activity could alter the balance among neurotoxic and neuroprotective oxysterols promoting motor neuron degeneration and/or immune response.

Cosmic-ray positron energy spectrum measured by PAMELA.

Precision measurements of the positron component in the cosmic radiation provide important information about the propagation of cosmic rays and the nature of particle sources in our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy. The combined measurements of the cosmic-ray positron energy spectrum and fraction provide a unique tool to constrain interpretation models. During the recent solar minimum activity period from July 2006 to December 2009, approximately 24,500 positrons were observed. The results cannot be easily reconciled with purely secondary production, and additional sources of either astrophysical or exotic origin may be required.

Marfan syndrome and aortic involvement: a narrative review.

Marfan syndrome (MFS) is a systemic connective tissue disease that commonly and most severely affects the ocular, skeletal, and cardiovascular systems. The aim of the manuscript is to review the aortic involvement and complications in MFS, including aortal dissection, thoracic aortic aneurysm, abdominal aortic aneurysm, and acute aortic syndrome. Dissecting thoracic aortic aneurysm and progressing aortic root enlargement are the major causes of MFS morbidity and mortality. Guidelines on aortic disease endorsed by the American College of Cardiology, and the American Heart Association recommend the measurement of the external and internal aortic diameters perpendicular to the axis of blood flow when Computed Tomography, or Magnetic Resonance Imaging, or Cardiac Echography are performed. The pathophysiology, diagnosis, prevention, and medical and surgical treatments of MFS associated with aortic complications are reported in this narrative review. Development and strengthening of centers specialized in cardiovascular diseases and MFS, together with an improvement in the knowledge of its pathogenesis through genetics and proteomics investigations, can ameliorate the prognosis of this disease.

New York Heart Association class and pulmonary artery pressure as prognostic factors of interstitial lung disease survival.

OBJECTIVE: The aim of this study was to evaluate New York Heart Association (NYHA) class and systolic pulmonary artery pressure (sPAP) as survival predictors in major interstitial lung diseases (ILD) including idiopathic pulmonary fibrosis (IPF), non-specific interstitial pneumonia (NSIP) and hypersensitivity pneumonitis (HP) and in other ILD like granulomatosis with polyangiitis (GPA). PATIENTS AND METHODS: We analyzed survival, NYHA class, sPAP, and Octreoscan uptake index (UI) in 104 ILD patients (59 IPF, 19 NSIP, 10 HP and 16 GPA; median age 60.5 years) all referred to a single centre. RESULTS: Median survival was 68 months, with 1- and 2-year survival of 91% and 78%, respectively. Survival was lower among IPF and NSIP vs. HP and GPA patients (p=0.01). NYHA class 3-4 was more frequent among IPF (76.3%) vs. NSIP patients (31.6%; p<0.001). HP and GPA had NYHA class 1-2. NYHA class was negatively associated with survival (class 1=90.3 months vs. class 3=18.3 months and class 4=5.1 months; p=0.001). sPAP was >55 mmHg in 76.3% of patients with IPF and 35-55 mmHg in 63.2% of patients with NSIP. Patients with HP and GPA had sPAP < 55 mmHg. Among patients with IPF, NYHA and sPAP were negatively associated with survival (p<0.01) both showed a parallel trend. High-resolution computed tomography and survival were worse among IPF and NSIP vs. HP and GPA patients (p<0.001). Octreoscan UI was <10, 10-12, and >12 in IPF, NSIP, HP and GPA, respectively. Octreoscan UI was negatively associated with survival (p=0.002). CONCLUSIONS: NYHA class and sPAP are comparable ILD survival predictors. NYHA class is correlated with worse prognosis for IPF and NSIP vs. HP and GPA patients.

Cosmic-ray electron flux measured by the PAMELA experiment between 1 and 625 GeV.

Precision measurements of the electron component in the cosmic radiation provide important information about the origin and propagation of cosmic rays in the Galaxy. Here we present new results regarding negatively charged electrons between 1 and 625 GeV performed by the satellite-borne experiment PAMELA. This is the first time that cosmic-ray e⁻ have been identified above 50 GeV. The electron spectrum can be described with a single power-law energy dependence with spectral index -3.18 ± 0.05 above the energy region influenced by the solar wind (> 30 GeV). No significant spectral features are observed and the data can be interpreted in terms of conventional diffusive propagation models. However, the data are also consistent with models including new cosmic-ray sources that could explain the rise in the positron fraction.

Stem cells therapy in acute myocardial infarction: a new era?

Stem cells transplantation after acute myocardial infarction (AMI) has been claimed to restore cardiac function. However, this therapy is still restricted to experimental studies and clinical trials. Early un-blinded studies suggested a benefit from stem cell therapy following AMI. More recent blinded randomized trials have produced mixed results and, notably, the last largest pan-European clinical trial showed the inconclusive results. Furthermore, mechanisms of potential benefit remain uncertain. This review analytically evaluates 34 blinded and un-blinded clinical trials comprising 3142 patients and is aimed to: (1) identify the pros and cons of stem cell therapy up to a 6-month follow-up after AMI comparing benefit or no effectiveness reported in clinical trials; (2) provide useful information for planning future clinical programs of cardiac stem cell therapy.

PAMELA results on the cosmic-ray antiproton flux from 60 MeV to 180 GeV in kinetic energy.

The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray antiproton flux and the antiproton-to-proton flux ratio which extends previously published measurements down to 60 MeV and up to 180 GeV in kinetic energy. During 850 days of data acquisition approximately 1500 antiprotons were observed. The measurements are consistent with purely secondary production of antiprotons in the Galaxy. More precise secondary production models are required for a complete interpretation of the results.

Predictors of survival in idiopathic interstitial pneumonia.

AIM: To evaluate the ability of newly identified clinical factors to predict prognosis and survival in idiopathic pulmonary fibrosis (IPF) and non-specific interstitial pneumonia (NSIP). METHODS: Seventy-eight patients referred to the University of Genoa and the Regional Hospital of Aosta between January 1995 and December 2006 were evaluated prospectively. Fifty-nine patients were diagnosed with IPF and 19 with NSIP on the basis of surgical lung biopsy specimens. Gender, age at diagnosis, smoking, New York Heart Association class (NYHA), systolic pulmonary artery pressure (sPAP), Octreoscan uptake index (UI), and therapy were the chosen variables. Primary end-point was survival. RESULTS: With the exception of gender and smoking history, all baseline patient characteristics correlated significantly with the diagnosis (IPF vs. NSIP). Median survival for the entire study group was 52.7 months. Univariate analysis showed poorer survival for the IPF group versus the NSIP group, and survival was significantly lower for older patients (p < 0.001). Multivariate analysis confirmed the negative prognostic effect of age (p < 0.001) on survival with a risk of death for older patients ( > OR =66 years old) being more than 4 times higher than that for younger patients (<58 yr.). NYHA class and pulmonary artery pressure were also significant predictors of survival, and all patients with a sPAP < OR = 35-mm Hg were alive at the end of the follow-up period. There was a good correlation between Octreoscan uptake index and the diagnosis. CONCLUSION: Diagnosis (IPF vs. NSIP), NYHA class, sPAP, and especially age appear to represent important prognostic indicators in the two most prevalent forms of idiopathic pulmonary fibrosis (IPF and NSIP). Lower Octreoscan uptake values were found in all patients with IPF, suggesting that this test may have a role as a new predictor of survival for differentiating IPF from NSIP.

New York Heart Association class associated with imaging is a prognostic mortality risk predictor in interstitial lung diseases.

OBJECTIVE: Mortality risk factors as forced vital capacity, diffuse lung capacity for carbon monoxide, and 6-minutes' walk test were studied in clinical trials monitoring patients affected by interstitial lung diseases (ILD). However, these parameters showed scarce accuracy. Our aim was to identify New York Heart Association (NHYA) class, in association with high resolution computed tomography (HRCT) and somatostatin receptor scintigraphy (Octreoscan), as a prognostic mortality risk factor in ILD patients. PATIENTS AND METHODS: Study population comprised 128 ILD patients (78 Males and 50 Females). Histological diagnosis was usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP) and granulomatous lung disease in 59, 19 and 50 patients, respectively. Patients were monitored by NYHA class, HRCT and Octreoscan at baseline and every 3 years up to a 10-year follow up. Overall survival was calculated from the date of diagnosis until death or last follow-up update. Statistical analysis was performed using Kaplan-Meier, log-rank test (LRT), multivariate analysis with Cox proportional hazard regression model, and log-likelihood ratio test. RESULTS: Overall median survival was 89.3 months (7.4 years) with the poorer survival rate observed in UIP patients. NYHA class came out as a reliable prognostic mortality risk factor in each group of patients and prognosis was progressively worse with NYHA class increase (LRT p<0.001). A strong correlation was found between NYHA class and age, CT-score, and Octreoscan in UIP patients (p<0.001). CONCLUSIONS: The determination of NYHA class can therefore be recommended as an additional prognostic mortality risk factor in ILD patients.

Phase II study of pemetrexed in combination with carboplatin in patients with malignant pleural mesothelioma (MPM).

BACKGROUND: The aim of this study was to evaluate the activity and toxicity of pemetrexed and carboplatin combination as first-line chemotherapy in malignant pleural mesothelioma (MPM). PATIENTS AND METHODS: Patients with measurable advanced MPM and a zero to two Eastern Cooperative Oncology Group (ECOG) performance status (PS) were enrolled. The schedule was pemetrexed 500 mg/m(2) in combination with carboplatin area under the curve 5, every 21 days. In all, 76 patients were treated. Median age was 65 years; median ECOG PS was zero. RESULTS: Grade 3 hematological toxicity according to World Health Organization criteria was seen in 36 (47.3%) patients; grade 4 hematological toxicity in 5 (6.5%) patients. There were 16 (21%) partial responses and 3 (4%) complete responses, for an overall response rate of 19 (25%) [95% confidence interval (CI) 15.3-34.7]. In all, 29 (39%) (95% CI 28-48) patients reported stable disease. The median survival was estimated at 14 months. CONCLUSION: This combination of carboplatin and pemetrexed is moderately active and the toxicity is acceptable.

Predictors of mortality of idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF), a disease with histological features corresponding to usual interstitial pneumonia (UIP), is a disorder of unknown cause. Not only it is the most common subtype of idiopathic interstitial pneumonias but it is also associated with the highest mortality rate. Despite a good number of studies investigating the mortality of patients with UIP the prognostic factors that have been studied have several limitations. To date it is unclear when in the course of the disease and with what modality these patients should be treated. According to the literature we subcategorized predictors of mortality into (a) baseline predictors; (b) dynamic predictors. IPF perspectives in therapy have been also analyzed. Moreover, the principal aims of this review were: (1) to analyze and to clarify the clinical utility of different prognostic factors for IPF; (2) to enable clinicians to better evaluate the eligibility criteria for lung transplantation in the clinical practice.

Synergistic differentiation-promoting activity of interferon gamma and tumor necrosis factor-alpha: role of receptor regulation on human neuroblasts.

BACKGROUND: Interferon gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF) synergize in inducing human neuroblastoma cells to differentiate terminally in vitro into mature nonproliferating neurons. The mechanisms by which this synergistic activity takes place are still obscure. PURPOSE: To understand the basis of IFN-gamma-TNF synergism, we investigated the constitutive equipment of receptors to IFN-gamma and TNF in two human neuroblastoma cell lines (i.e., LAN-5 and GI-LI-N) and their quantitative and functional variations following treatment with IFN-gamma or TNF. METHODS: IFN-gamma receptors and TNF receptors were assessed and functionally characterized by radioreceptor-binding assay before and after treatment of the cells with IFN-gamma or TNF. The TNF receptor subtypes were identified by the reverse transcriptase-polymerase chain reaction, chemical cross-linking of receptors to iodinated TNF, and inhibition of TNF binding by type-specific anti-TNF receptor monoclonal antibodies. The effects of cytokines on cell differentiation were assessed by thymidine incorporation inhibition and morphologic maturation. RESULTS: No quantitative or functional modification of IFN-gamma receptors was observed in TNF-treated cells. However, after treatment with IFN-gamma, TNF receptor numbers were enhanced to a different extent in both cell lines. The two neuroblastoma cell lines expressed, both constitutively and after IFN-gamma induction, only one species of TNF receptor, i.e., the p80 form in LAN-5 and the p60 form in GI-LI-N. Sequential treatment with IFN-gamma followed by TNF, but not in the opposite order, could reproduce the early effects of differentiation in neuroblastoma cells, supporting a role for TNF receptor up-regulation as a basis for the cooperation between the two cytokines. CONCLUSION: The results strongly suggest that receptor regulation can be at least one mechanism by which IFN-gamma and TNF exert their synergistic effects. Moreover, it appears that the two TNF receptor types are redundant in signaling neuroblastoma cell differentiation. IMPLICATIONS: Our findings can provide a guideline for a rational design of experimental differentiation-based therapeutic protocols in patients with neuroblastoma.

gamma-Interferon increases metaiodobenzylguanidine incorporation and retention in human neuroblastoma cells.

Iodine-labeled m-iodobenzylguanidine (MIBG) is a widely used radiopharmaceutical for both diagnosis and biologically targeted radiotherapy of neuroblastoma. However, resistance to the radiotherapeutic effects of MIBG is often encountered, mainly due to lack of MIBG accumulation by neoplastic cells. We have investigated whether the induction of neuroblastoma cell differentiation modifies MIBG incorporation and retention. LAN-5 cells were selected, due to their moderate ability to take up MIBG. Treatment of these cells with gamma-interferon (IFN-gamma) resulted in morphological changes accompanied by a significant increase in overall cell-associated MIBG. Desimipramine, but not reserpine, easily depleted IFN-gamma-treated LAN-5 cells of their MIBG content. This suggests that the mechanism involved is an uptake enhancement rather than an improved storage ability. Indeed, IFN-gamma induces de nov synthesis of MIBG receptor-transporters, as demonstrated by polymerase chain reaction amplification and semiquantitative analysis. Our results suggest that pretreating neuroblastoma patients with IFN-gamma before MIBG administration may enhance the efficacy of both biologically targeted radioimaging and therapy of this tumor.

eps15 and eps15R are essential components of the endocytic pathway.

eps15 and eps1SR are substrates of the epidermal growth factor (EGF) receptor kinase that are characterized by the presence of a protein:protein interaction domain, the EH domain, and by their ability to bind to the clathrin adaptor protein complex adaptor protein 2. Indirect evidence suggests that eps15 and eps15R are involved in endocytosis. Here we show that microinjection of antibodies against eps15 and eps15R inhibits internalization of EGF and transferrin. In addition, fragments of eps15 (encompassing its EH domains or the COOH-terminal region that binds to adaptor protein 2) inhibit EGF internalization or endocytosis of Sindbis virus. These results demonstrate that eps15 and eps15R are essential components of the endocytic machinery.

The localization of the HRX/ALL1 protein to specific nuclear subdomains is altered by fusion with its eps15 translocation partner.

Translocations involving the HRX/ALL1 locus at chromosomal region 11q23 are among the most frequent cytogenetic abnormalities in acute leukemias. 11q23 translocations involve different chromosome partners and lead to the formation of HRX/ALL1 fusion proteins. The HRX/ALL1 protein is a putative transcription factor that has been implicated in developmental regulation in mammals. We report here the cellular localization of the HRX/ALL1 protein as well as that of the HRX/ALL1-eps15 fusion protein, the result of the t(1;11) (p32-q23) translocation of acute myeloid leukemias. The HRX/ALL1 protein was localized to both the cytoplasm and the nucleus. The nuclear pattern was characterized by diffuse staining, perinuclear accumulation, and localization within nuclear bodies of variable size, morphology, and number. The HRX/ALL1-eps15 localized exclusively to the nucleus within bodies that were smaller and more numerous than the HRX/ALL1 nuclear bodies. HRX/ALL1 fusion with an unknown partner in leukemia blasts with 11q23 abnormalities had similar morphological features. Thus, the fusion with eps15 alters the cellular compartmentalization of HRX/ALL1, providing a putative mechanism for activation of HRX/ALL1 by 11q23 abnormalities.

Regulation of the tyrosine kinase substrate Eps8 expression by growth factors, v-Src and terminal differentiation.

SH3-containing proteins are involved in signal transduction by a number of growth factor receptors and in the organization of the cytoskeleton. The recently identified Eps8 protein, which contains an SH3 domain, is coupled functionally and physically to the EGFR and is tyrosine phosphorylated by this receptor and other receptors as well. Here, we examined the regulation of eps8 expression in response to mitogenic or differentiative signals. We show that Eps8 is expressed at low levels in resting fibroblasts, but its expression is strongly induced during activation by serum, phorbol esters and the v-src oncogene. Conversely, expression of Eps8, but not of other EGFR substrates such as Shc or Eps15, is virtually extinguished in non-proliferating, terminally differentiated murine myogenic cells. The putative role of Eps8 protein as a v-Src substrate was analysed in murine fibroblasts and in quail myogenic cells expressing a temperature-sensitive variant of the tyrosine kinase. Tyrosine phosphorylation of Eps8 was detected only at the permissive temperature. A non-myristylated, transformation-defective mutant of v-Src did not phosphorylate Eps8, whereas it phosphorylated Shc. Together, these findings indicate that Eps8 may be a critical substrate of v-Src. They further establish Eps8 as an example of a signal transducer whose expression senses the balance between growth and differentiation and might, therefore, be involved in the determination of the phenotype.

Cytotoxicity and differentiating actions of adriamycin in WEHI-3B D+ leukemia cells.

The monomyelocytic leukemia WEHI-3B D+ can be induced to differentiate into mature granulocytes in suspension culture when exposed to 40 nM adriamycin. Treated cells underwent approximately two divisions prior to reaching plateau phase, with approximately 55% of the cell population expressing nitro blue tetrazolium positivity (NBT+) by day 3. Decreased cellular proliferation was paralleled by a progressive increase in morphologically mature granulocytic cells. Maturation was also characterized by a 4.4-fold increase in Fc receptors on the cell surface. An increase in the size of adriamycin-treated cells occurred and correlated with residency in the G2M phase of the cell cycle. Adriamycin-induced NBT+ cells, which contained the highest levels of Fc receptors, were also found to reside in G2M. Adriamycin blocked cells in the G2M phase of the cell cycle by 8 hr (125% above control), and this arrest reached its maximum by 20 hr (194% above control). Concomitant with the block in the cell cycle was the commitment by these cells within 8 hr to the granulocytic pathway of differentiation. Fractionation of cells by centrifugal elutriation into enriched phases of the cell cycle was consistent with the hypothesis that induction of the differentiation program was initiated either in G1 or very late in the cell cycle. Immobilized adriamycin, which does not gain access to the cell interior, did not induce the maturation of WEHI-3B D+ cells, nor did it block their replication in a specific phase of the cell cycle; however, immobilized adriamycin was 30-fold more toxic to WEHI-3B D+ cells than free drug. Incubation of WEHI-3B D+ cells with the semisynthetic adriamycin analog N-trifluoroacetyl adriamycin-14-valerate (AD-32) resulted in approximately 50% of the cell population being NBT+ by day 3. The findings suggest that adriamycin must be able to enter cells to induce maturation, and that at least some portion of its toxicity is associated with an effect at the surface membrane. Furthermore, the results obtained with AD-32 imply that intercalation into DNA is not necessary for induction of the differentiated phenotype.