Fungal infections of the central nervous system and paranasal sinuses in onco-haematologic patients. Epidemiological study reporting the diagnostic-therapeutic approach and outcome in 89 cases.

Invasive fungal infections (IFI) of the Central Nervous System (IFI-CNS) and Paranasal Sinuses (IFI-PS) are rare, life-threatening infections in haematologic patients, and their management remains a challenge despite the availability of new diagnostic techniques and novel antifungal agents. In addition, analyses of large cohorts of patients focusing on these rare IFI are still lacking. Between January 2010 and December 2016, 89 consecutive cases of Proven (53) or Probable (36) IFI-CNS (71/89) and IFI-PS (18/89) were collected in 34 haematological centres. The median age was 40 years (range 5-79); acute leukaemia was the most common underlying disease (69%) and 29% of cases received a previous allogeneic stem cell transplant. Aspergillus spp. were the most common pathogens (69%), followed by mucormycetes (22%), Cryptococcus spp. (4%) and Fusarium spp. (2%). The lung was the primary focus of fungal infection (48% of cases). The nervous system biopsy was performed in 10% of IFI-CNS, and a sinus biopsy was performed in 56% of IFI-PS (P = 0.03). The Galactomannan test on cerebrospinal fluid has been performed in 42% of IFI-CNS (30/71), and it was positive in 67%. Eighty-four pts received a first-line antifungal therapy with Amphotericine B in 58% of cases, Voriconazole in 31% and both in 11%. Moreover, 58% of patients received 2 or more lines of therapy and 38% were treated with a combination of 2 or more antifungal drugs. The median duration of antifungal therapy was 60 days (range 5-835). A surgical intervention was performed in 26% of cases but only 10% of IFI-CNS underwent neurosurgical intervention. The overall response rate to antifungal therapy (complete or partial response) was 57%, and 1-year overall survival was 32% without significant differences between IFI-CNS and IFI-PS. The overall mortality was 69% but the IFI attributable mortality was 33%. Mortality of IFI-CNS/PS remains high but, compared to previous historical data, it seems to be reduced probably due to the availability of newer antifungal drugs. The results arising from this large contemporary cohort of cases may allow a more effective diagnostic and therapeutic management of these very rare IFI complications in haematologic patients.

Ethanol, O, and CO adsorption on Pt nanoparticles: effects of nanoparticle size and graphene support.

Pt nanoparticles dispersed over carbonaceous supports are widely used as catalysts for different applications, making studies on the interplay between size and support effects indispensable for rational catalyst design. Here, we use DFT calculations to simulate the interaction between O, CO, and ethanol with free platinum cuboctahedral nanoparticles with up to 147 atoms and with the same Pt nanoparticles supported on a single layer of graphene with up to 720 carbon atoms. We compute adsorption energies for each adsorbate on different adsorption sites for supported and unsupported Pt nanoparticles. We show that as the Pt nanoparticle grows the adsorption energy decreases, and that the size effect is more important for O and CO adsorption than for ethanol. We observe that the generalized coordination number of each adsorption site controls the interaction strength for O and CO to a much larger extent than for ethanol. Electronic charge redistributions and density of states projected on the d band of the interacting Pt facets are used to obtain a better understanding of the differences between the electronic interactions for each adsorbate. For Pt nanoparticles supported on graphene, the support effects weaken the adsorption energies for all the adsorbates, but this effect rapidly decreases with larger nanoparticles, and it is only significant for our smallest nanoparticle Pt13. By demonstrating that the effects of nanoparticle size and support are different for ethanol as compared with O and CO, we conclude that it should be possible to modify different parameters in the catalyst design in order to tune the Pt nanoparticle to interact with specific adsorbates.

DFT calculation of oxygen adsorption on platinum nanoparticles: coverage and size effects.

Catalysts made of Pt nanoparticles and Pt alloys are considered state-of-the-art catalysts for the anodic and cathodic reactions involved in hydrogen fuel cells. The optimal size of such nanoparticles for each chemical reaction is an unsolved problem that depends on environmental variables, such as reactant concentration, solvent, temperature, etc. From a theoretical point of view, this problem has been tackled mainly by observing how single key adsorbates react with different nanoparticles under controlled conditions. In this work, we use large-scale DFT calculations to examine the interplay between the Pt nanoparticle size and O coverage effects. We examine single O adsorptions for three adsorption sites on cuboctahedral platinum nanoparticles with different sizes. As we grow the nanoparticle size, the binding strength decreases and we observed a quick convergence of the adsorption energies with increasing nanoparticle size, which correlates with the calculated d-band centre for (111) Pt facets on such nanoparticles. We also carried out a detailed study of the effect of oxygen coverage with varying fractions of O monolayer coverage, computing adsorption energies per O atom for Pt55, Pt147 and Pt309 nanoparticles with several O coverages. In general, an increase of O coverage led to weaker adsorption energies per O atom, and when analysing the results in terms of oxygen monolayers, this effect is more pronounced for larger nanoparticles. The O coverage dependency of the adsorption energy per O atom is analysed in terms of the O distribution for each nanoparticle size and electronic changes that the adsorbed oxygen causes to the Pt nanoparticle. In studying nanoparticle size and oxygen coverage effects simultaneously, we offer insights with DFT accuracy to help on heterogeneous catalyst design.

Effect of graphene support on large Pt nanoparticles.

State-of-the-art catalysts are often created via deposition of monolayers, sub-monolayers or nanoparticles of the catalytic material over supports, aiming to increase the surface area and decrease the loading of the catalytic material and therefore the overall cost. Here, we employ large-scale DFT calculations to simulate platinum clusters with up to 309 atoms interacting with single layer graphene supports with up to 880 carbon atoms. We compute the adsorption, cohesion and formation energies of two and three-dimensional Pt clusters interacting with the support, including dispersion interactions via a semi-empirical dispersion correction and a vdW functional. We find that three-dimensional Pt clusters are more stable than the two-dimensional when interacting with the support, and that the difference between their stabilities increases with the system size. Also, the dispersion interactions are more pronounced as we increase the nanoparticle size, being essential to a reliable description of larger systems. We observe inter-atomic expansion (contraction) on the closest (farthest) Pt facets from the graphene sheet and charge redistribution with overall charge being transferred from the platinum clusters to the support. The Pt-Pt expansion, which is related to the charge transfer in the system, correlates with the adsorption energy per Pt atom in contact with the graphene. These, and other electronic and structural observations show that the effect of the support cannot be neglected. Our study provides for the first time, to the best of our knowledge, quantitative results on the non-trivial combination of size and support effects for nanoparticles sizes which are relevant to catalyst design.

Emerging resistant bacteria strains in bloodstream infections of acute leukaemia patients: results of a prospective study by the Rete Ematologica Lombarda (Rel).

Multiresistant bacterial infections are a potentially life-threatening condition in acute leukaemia (AL) patients. We aimed to better define the very recent epidemiology and outcome of bloodstream infections (BSIs) in a real-life setting. We prospectively collected all consecutive febrile/infectious episodes occurring in AL patients admitted to 9 haematology units. In 293 AL patients, 433 BSIs were diagnosed. Gram-positive (GP) bacteria were isolated in 44.8 % BSI and Gram-negative (GN) in 38.3 %, while polymicrobial aetiology- or fungi-related events were identified in 15.7 and 1.1 % of the cases, respectively. GP was observed more frequently in patients not in complete remission (p = 0.04), while GN during consolidation cycles (p = 0.003). Extended spectrum ß-lactamase-producing strains accounted for 23.2 % of enterobacteria. They were associated with previous antibiotic exposure, including fluoroquinolones prophylaxis (p = 0.01). Carbapenem-resistant (CR) strains occurred in 9 % of enterobacteria. Among Pseudomonas aeruginosa strains, 21.6 % were multiresistant. Overall 30-day mortality was 8.5 %. CR GN and multiresistant P. aeruginosa BSIs were independent predictors of death (p = 0.002), as well as relapsed/resistant AL (18.3 %; p = 0.0002) and the presence of pulmonary infiltrates (26.6 %; p < 0.001). Although GP still predominate over GN BSI, the percentage of antibiotic resistant GN strains is considerable in AL patients and it is associated with poor prognosis.

Cytomegalovirus infection after autologous stem cell transplantation: incidence and outcome in a group of patients undergoing a surveillance program.

This study was performed to evaluate the incidence, risk factors, and outcome of cytomegalovirus (CMV) infection in autologous stem cell transplantation (ASCT), with the aim of performing preemptive therapy in patients with antigenemia. Starting from 2001, 171 consecutive ASCTs were performed in 136 patients; 102 of these patients were seropositive for CMV at the onset of hematological disease. In all these patients, a CMV pp65 antigenemia assay was determined weekly, starting from the day when the absolute neutrophil count went above 500/microL, and until day 60 after ASCT; subsequently, antigenemia was determined only when a CMV infection was suspected. Among the 136 transplanted patients, 40 (29.4%) presented a positive antigenemia; all of them were seropositive for CMV before ASCT; and no cases of primary infection were seen. The incidence of CMV infection in the seropositive population was 40/102 (39.3%); 6 patients (5 with multiple myeloma and 1 with non-Hodgkin's lymphoma) who received 2 ASCTs developed CMV infections after both transplantations, so that positive antigenemia developed after 46/171 (26.9%) transplantations. First positive antigenemia presented a median of 32 days (range 7-57) after stem cell reinfusion. The median antigenemia level at the first appearance was 2/200,000 (range 1-1000). No significant prognostic factors could be shown. Enteritis was present in 5 patients; 2 of them also had fever, and 1 of them also had thrombocytopenia. In 5 patients fever without any other clinical signs or symptoms was present; 30 patients were asymptomatic. Fourteen patients were treated with anti-CMV drugs. CMV reactivation was successfully treated in all patients, and no patient died from CMV disease.

Selection of patients for carotid endarterectomy: the role of ultrasound.

Stroke is the third leading cause of death in the western world and the major cause of disability among the middle aged and elderly populations. Carotid artery stenosis is the single most important risk factor for stroke. The North American Symptomatic Carotid Endarterectomy Trial and the European Carotid Surgery Trial have demonstrated that the risk of stroke is reduced by surgery in patients with high grade stenosis. Carotid plaque morphology also plays an important role; plaques which are ulcerated and echolucent are associated with a higher risk of stroke. Arteriography has long been regarded as the gold standard diagnostic tool for evaluation of carotid artery disease, but it is an invasive and costly technique which carries the risk of potentially serious complications. Doppler ultrasound can provide functional and anatomical information on vessel stenosis and plaque morphology at sub-millimetric resolutions and is an inexpensive and noninvasive tool. Color and spectral Doppler ultrasound are now recognized as the best screening tests for carotid artery stenosis. The evidence for its use as the sole diagnostic imaging modality prior to carotid endarterectomy is examined. The recent availability of ultrasound contrast agents helps to distinguish between pseudo- and true occlusions, improves ultrasound images and should help to reduce operator variability.

Lipoblastoma and lipoblastomatosis in children.

Lipoblastoma and lipoblastomatosis are rare mesenchymal benign tumors of embryonal white fat. They are found primarily in children less than 5 years of age. This tumor presents in two forms: a localized well-circumscribed lesion (lipoblastoma), or a multicentric type (lipoblastomatosis). The authors presents three cases, two of them with a buttock lesion, the last with a paravertebral one. It is recommended a complete but conservative excision of the tumor because there is a natural tendency to involution, although in the first year of life a local reexcision for recurrence is sometimes described.

The new apolipoprotein A-I variant leu(174) --> Ser causes hereditary cardiac amyloidosis, and the amyloid fibrils are constituted by the 93-residue N-terminal polypeptide.

We identified a novel missense mutation in the apolipoprotein A-I gene, T2069C Leu(174) --> Ser, in a patient affected by familial systemic nonneuropathic amyloidosis. The amyloid deposits mostly affected the heart of the proband, who underwent transplantation for end-stage congestive heart failure. Amyloid fibrils of myocardial and periumbilical fat samples immunoreacted exclusively with anti-ApoA-I antibodies. Amyloid fibrils extracted from the heart were constituted, according to amino acid sequencing and mass spectrometry analysis, by an amino-terminal polypeptide ending at Val(93) of apolipoprotein A-I (apoA-I); no other significant fragments were detected. The mutation segregates with the disease; it was demonstrated in the proband and in an affected uncle and excluded in three healthy siblings. The plasma levels of high-density lipoprotein and apoA-I were significantly lower in the patient than in unaffected individuals. This represents the first case of familial apoA-I amyloidosis in which the mutation is outside the polypeptide fragment deposited as fibrils. Visualization of the mutation in the three-dimensional structure of lipid-free apoA-I, composed of four identical polypeptide chains, indicates that position 174 of one chain is located near position 93 of an adjacent chain and suggests that the amino acid replacement in position 174 is permissive for a proteolytic split at the C-terminal of Val(93).

Infantile neuroaxonal dystrophy: neuroradiological studies in 11 patients.

We report the imaging findings in 11 patients with infantile neuroaxonal dystrophy. Ten patients underwent 15 MRI examinations; one patient had only CT. Of the ten patients who underwent MRI, eight had cerebellar atrophy and mildly increased signal from the cerebellar cortex on T2-weighted images. With T2 weighting there was slightly increased signal from the dentate nuclei in two patients and from the posterior periventricular white matter in three. We saw four patients with a thin optic chiasm. The only two brothers in the series had markedly low signal from the globus pallidus and substantia nigra on 1.5 T T2-weighted images, as seen in Hallervorden-Spatz disease (HSD). Abnormalities of the globus pallidus may be related to a protracted course of the disease. However, an overlap with HSD should be considered.

Infantile neuroaxonal dystrophy: clinical spectrum and diagnostic criteria.

OBJECTIVE: To present clinical, neurophysiologic, and neuroradiologic findings in 13 patients with infantile neuroaxonal dystrophy (INAD), focusing on aspects that assist early diagnosis. BACKGROUND: Clinicopathologic diagnostic criteria for INAD were delineated by Aicardi and Castelein in 1979, but atypical cases are reported frequently and little is known of the diagnostic utility of MRI. METHODS: The authors reviewed the clinical, neurophysiologic, and MRI findings of 13 patients who met the diagnostic criteria for INAD. RESULTS: Symptoms onset was between 6 months and 2 years of age. In nine patients the clinical course was typical, with rapid motor and mental deterioration; in four patients progression was slower and the clinical picture was different. Electromyographic (EMG) signs of chronic denervation, fast rhythms on EEG and abnormal visual evoked potentials were observed in all patients during the disease course. Cerebellar atrophy with signal hyperintensity in the cerebellar cortex on T2-weighted images were the most characteristic MRI findings; hypointensity in the pallida and substantia nigra was also observed in two patients. alpha-N-acetyl-galactosaminidase activity on leukocytes was normal in the 10 patients tested. CONCLUSIONS: EMG and MRI abnormalities are the earliest and most suggestive signs of INAD, which has a clinical and radiologic spectrum that is broader than reported previously.

Stem cell factor in mast cells and increased mast cell density in idiopathic and ischemic cardiomyopathy.

BACKGROUND: We compared cardiac mast cell (HHMC) density and the immunological and nonimmunological release of mediators from mast cells isolated from heart tissue of patients with idiopathic dilated (DCM) (n=24) and ischemic cardiomyopathy (ICM) (n = 10) undergoing heart transplantation and from control subjects (n = 10) without cardiovascular disease. METHODS AND RESULTS: HHMC density in DCM (18.4+/-1.6 cells/mm2) and ICM (18.4+/-1.5 cells/mm2) was higher than that in control hearts (5.3+/-0.7 cells/mm2; P<.01). The histamine and tryptase contents of DCM and ICM hearts were higher than those of control hearts. The histamine content of the hearts was correlated with mast cell density (r(s)=.91; P<.001). Protein A/gold staining of heart tissue revealed stem cell factor (SCF), the principal growth, differentiating, and activating factor of human mast cells, in HHMC secretory granules. Histamine release from cardiac mast cells caused by immunological (anti-IgE and rhSCF) and nonimmunological stimuli (Ca2+ ionophore A23187) was higher in patients with DCM and ICM compared with control subjects. Immunological activation of HHMC induced a significantly greater release of tryptase and LTC4 in patients with DCM and ICM compared with control subjects. CONCLUSIONS: Histamine and tryptase content and mast cell density are higher in failing hearts than in control hearts. SCF, present in secretory granules of HHMC, might represent an autocrine factor sustaining mast cell hyperplasia in heart tissue in these patients. The increased local release of fibrogenic factors (eg, histamine, tryptase, and leukotriene C4) might contribute to collagen accumulation in the hearts of patients with cardiomyopathy.

Restrictive cardiomyopathy, atrioventricular block and mild to subclinical myopathy in patients with desmin-immunoreactive material deposits.

OBJECTIVES: We present clinical data and heart and skeletal muscle biopsy findings from a series of patients with ultrastructural accumulations of granulofilamentous material identified as desmin. BACKGROUND: Desmin cardiomyopathy is a poorly understood disease characterized by abnormal desmin deposits in cardiac and skeletal muscle. METHODS: Clinical evaluation, endomyocardial and skeletal muscle biopsy, light and electron microscopy and immunohistochemistry were used to establish the presence of desmin cardiomyopathy. RESULTS: Six hundred thirty-one patients with primary cardiomyopathy underwent endomyocardial biopsy (EMB). Ultrastructural accumulations of granulofilamentous material were found in 5 of 12 biopsy samples from patients with idiopathic restrictive cardiomyopathy and demonstrated specific immunoreactivity with anti-desmin antibodies by immunoelectron microscopy. Immunohistochemical findings on light microscopy were nonspecific because of a diffuse intracellular distribution of desmin. All five patients had atrioventricular (AV) block and mild or subclinical myopathy. Granulofilamentous material was present in skeletal muscle biopsy samples in all five patients, and unlike the heart biopsy samples, light microscopic immunohistochemical analysis demonstrated characteristic subsarcolemmal desmin deposits. Two patients were first-degree relatives (mother and son); another son with first-degree AV block but without myopathy or cardiomyopathy demonstrated similar light and ultrastructural findings in skeletal muscle. Electrophoretic studies demonstrated two isoforms of desmin--one of normal and another of lower molecular weight--in cardiac and skeletal muscle of the familial cases. CONCLUSIONS: Desmin cardiomyopathy must be considered in the differential diagnosis of restrictive cardiomyopathy, especially in patients with AV block and myopathy. Diagnosis depends on ultrastructural examination of EMB samples or light microscopic immunohistochemical studies of skeletal muscle biopsy samples. Familial desminopathy may manifest as subclinical disease and may be associated with abnormal isoforms of desmin.

Heterotopic pancreatic tissue at umbilicus.

Heterotopic pancreatic tissue at the umbilicus is a very rare anomaly with only 4 cases previously reported in the literature: we describe our experience with 2 additional cases.

[A follow-up study in individuals subjected to ileo-cecal resection in infancy and childhood]. / Controlli a distanza di individui sottoposti in età pediatrica a resezioni intestinali interessanti anche la valvola ileo-cecale.

It is stated that the ileocecal valve delays the passage of ileal contents into the cecum and acts as a barrier against reflux and ascension of colonic bacterial flora into the small bowel: its resection may lead to bacterial colonization of the ileum and to abnormalities of intestinal motility, transit and absorption. In this study twenty individuals subjected in pediatric age (1 day to 11 years) to ileocecal resection have been evaluated from 2 to 19 years after surgery. Three patients underwent limited ileocecal resection, in four this was associated with a significant ileal resection, in five with extensive right colon resection and in eight with extensive ileal and right colon resection. Growth, stool habit, hematology and serum biochemistry were examined; all patients also underwent abdominal ultrasonography. In all body weight and height were within normal limits; seven had moderate diarrhea up to 18 months after surgery and two who required extensive intestinal resection (40 and 30 cm of small bowel left) had diarrhea until about 36 months after surgery: now all of them have daily fecal evacuation. Hematological, biochemical, urinary and fecal studies proved normal except in one treated with TPN who presented transaminases slightly increased and in three suffering from mucoviscidosis in whom steatorrhea with moderate alterations of fats and elevation of alkaline phosphatase and transaminases were present. Urinary and gall stones were not seen in anyone. In conclusion from this study it can be postulated that removal of ileocecal valve can be done safely in children.