Biotechnological applications of nanostructured hybrids of polyamine carbon quantum dots and iron oxide nanoparticles.

The combination of different nanomaterials has been investigated during the past few decades and represents an exciting challenge for the unexpected emerging properties of the resulting nano-hybrids. Spermidine (Spd), a biogenic polyamine, has emerged as a useful functional monomer for the development of carbon quantum dots (CQDs). Herein, an electrostatically stabilized ternary hybrid, constituted of iron oxide-DNA (the core) and spermidine carbon quantum dots (CQDSpds, the shell), was self-assembled and fully characterized. The as-obtained nano-hybrid was tested on HeLa cells to evaluate its biocompatibility as well as cellular uptake. Most importantly, besides being endowed by the magnetic features of the core, it displayed drastically enhanced fluorescence properties in comparison with parent CQDSpds and it is efficiently internalized by HeLa cells. This novel ternary nano-hybrid with multifaceted properties, ranging from fluorescence to superparamagnetism, represents an interesting option for cell tracking.

Perioperative multidisciplinary management of endoscopic transsphenoidal surgery for sellar lesions: practical suggestions from the Padova model.

Perioperative management of patients with sellar lesion submitted to endoscopic transsphenoidal neurosurgery (TSS) lacks standardization and therefore it is committed to each center clinical practice. Although neurosurgical procedure remains the same for all sellar lesions, perioperative approach can require different measures depending on the underlying disease. With the aim of standardizing our perioperative procedures and sharing our experience with other centers involved in the management of pituitary disease, we developed a clinical care path for patients with sellar lesions candidate to endoscopic TSS. For the drafting of the following protocol, the national and international guidelines published in the last 5 years have been evaluated and integrated with our center experience accumulated in decades of clinical practice. A steering committee including medical doctors involved in management of patients with pituitary masses at the Padua Hospital reviewed current knowledge on this topic. The committee developed a first draft which was shared with a broader group of medical doctors to reach a preliminary consensus; when it was reached, the clinical care assistance pathway was confirmed, validated, and published in the local web-based health service. We want to present and share our experience with colleagues involved in the perioperative management of pituitary diseases in other centers.

Electrostatically stabilized hybrids of carbon and maghemite nanoparticles: electrochemical study and application.

Binary hybrids have been investigated for the past few decades due to the emerging properties of nanoparticle composites. Electrostatically stabilized core-shell nanostructures composed of surface active magnetic nanoparticles (SAMNs) and differently charged carbon nanomaterials display specific electrochemical properties. In this work, a set of binary hybrids that include a new class of magnetic nanoparticles is presented and the electrochemical features of the hybrids are reported. Gallic acid derived carbon dots (GA-CDs), PEG derived graphene dots (PEG-GDs), and quaternized carbon dots (Q-CDs) characterized by different charged groups were used for the preparation of different complexes with SAMNs. Thus, a set of six binary nanomaterials was obtained, and characterized by electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometry, demonstrating significant differences in the charge transfer resistance, capacitive current, electrochemical performance, and reversibility with respect to the isolated subunits. Among them, the combination of Q-CDs with an excess of SAMNs led to a Q-CD@SAMN hybrid, which displayed peculiar electrocatalytic properties attributable to the influence of the strong electrostatic interactions exerted by Q-CDs on the SAMN surface. Notwithstanding their small fraction (around 1% w/w), Q-CDs oriented the electrocatalysis of SAMNs toward the selective electro-oxidation of polyphenols at low applied potentials (+0.1 V vs. SCE). Finally, the Q-CD@SAMN hybrid was used for the development of a coulometric sensor for polyphenols, composed of a simple carbon paste electrode in a small volume electrochemical flow cell (1 µL), and used for the complete direct electro-oxidation of polyphenols from plant extracts.

Tuberculosis of the eye in Italy: a forgotten extrapulmonary localization.

PURPOSE: Tuberculosis (TB) of the eye is a well-known extrapulmonary localization in high-incidence countries. Data on its relevance in developed countries are scanty. We aim to study the epidemiological and clinical pattern of ocular TB in a tertiary care institution of a western country. METHODS: From 2007 to 2010, consecutive patients with a diagnosis of isolated ocular TB or associated to extraocular TB were recruited. Patients with ophthalmological and clinical features of TB were treated with standard antitubercular therapy (ATT) and steroids in case of concomitant severe ocular inflammation. RESULTS: Seventeen cases of ocular and extraocular TB and 45 cases of isolated ocular TB were identified. The proportion of patients with ocular and extraocular TB in our local district was 8.1 %, with a proportion of 10.6 % for the isolated cases. In Cohort 1, only one patient was symptomatic for ocular impairment, and uveitis without inflammation was the most common presentation. On the contrary, in Cohort 2, all patients had visual impairment, mainly with bilateral involvement. 77.8 % of the patients showed an inflammatory pattern. ATT was administered for at least 9 months, in four cases with a short course of systemic corticosteroids. Eight cases in Cohort 2 showed recurrence after 1 year from diagnosis. CONCLUSIONS: TB of the eye should not be forgotten, even in geographical areas not considered among endemic countries. Ocular evaluation is advisable in patients with pulmonary and extrapulmonary TB, as early detection may allow ATT to preserve visual acuity.

Sequential development of large B cell lymphoma in a patient with peripheral T-cell lymphoma.

Lymphomas of different histologic type can occur in the same patient. Two types of lymphomas can be diagnosed in the same lymph node (composite lymphoma) or in different sites. In the latter case, terms as simultaneous and sequential have been proposed to define the detection of two lymphomas at the same time or at different times, respectively.

Diagnostic and prognostic value of low percentage of glycosylated ferritin in acquired hemophagocytic lymphohistiocytosis: A single-center study.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is an aggressive and life-threatening syndrome characterized by an excessive immune activation. Glycosylated ferritin (GF) level has been proposed as highly specific of HLH. METHODS: We have studied 12 subjects with HLH according to the HLH-04 trial criteria and 11 patients with a clinical and laboratoristic suspicion of HLH. The percentage of GF was measured by an in-house assay. RESULTS: The only biomarkers that were significantly different in the two groups were fraction of GF (P<.001) and the presence of hemophagocytosis in bone marrow (P=.006). Subjects with HLH had significantly lower percentage of GF than patients with other inflammatory conditions mimicking HLH. A fraction of GF ≤20% was strongly consistent with a diagnosis of HLH. CONCLUSIONS: Fraction of GF is useful to identify subjects at high risk for early death and therefore in need of early treatment.

Hypertriglyceridemia during long-term interferon-alpha therapy in a series of hematologic patients.

Adverse reactions to interferon-alpha (IFN-alpha) therapy include flu-like syndrome, bone marrow suppression, neurotoxic effects, and autoimmunity. A slight increase in triglyceride levels has been described less frequently during IFN-alpha administration. The incidence of IFN-alpha-induced hypertriglyceridemia seems variable, and there are no clear data on how to treat it. We report the effect of long-term (more than 12 months) IFN-alpha treatment on triglyceride levels in 43 patients suffering from hairy cell leukemia (18), multiple myeloma (10), chronic myelogenous leukemia (6), cryoglobulinemia (5), non-Hodgkin's lymphoma (3), and Sezary syndrome (1). Hypertriglyceridemia was found in 6 patients (15%). In 3 patients, gemfibrozil restored normal triglyceride values. This study suggests that hypertriglyceridemia is a minor side effect of long-term IFN-alpha therapy and that gemfibrozil might be considered the treatment of choice.

Deuterium nuclear magnetic resonance for evaluating the metabolic status of livers subjected to warm ischemia.

BACKGROUND: The development of reliable methods for assessing the viability of currently available livers is expected to increase the number of successful transplantations. METHODS: 2 H nuclear magnetic resonance (NMR) was used to search for metabolic markers of ischemia in explanted rat livers. Deuterium oxide (2 H2O) was used as a source of 2 H. A total of 10-80% v/v 2 H2O was added to homogenates obtained from a liver biopsy and the formation of 2 H-labeled metabolites was monitored. RESULTS: Some well-resolved 2 H resonances were found in the homogenates from biopsies of warm ischemic liver. Two of these were identified as [3-2 H] lactate and [2-2 H] lactate, and a linear relationship was found between the ratio of [[2-2 H] lactate] to [[3-2 H] lactate] and the warm ischemia time. The deuterium incorporation into lactate was explained on the basis of the metabolic events occurring under hypoxic conditions. CONCLUSIONS: The experimental results support the application of 2 H NMR for a reliable evaluation of the metabolic status of a liver harvested from non-heart-beating donors.

Purification and characterization of two casein kinases from ejaculated bovine spermatozoa.

Two protein kinases active on casein and phosvitin were partially purified from the soluble fraction of ejaculated bovine spermatozoa. They were operationally termed casein kinase A and B based on the order of their elution from a phosphocellulose column. CK-A showed an approximate molecular mass of 38 kDa, and it phosphorylated serine residues of casein and phosvitin utilizing ATP as a phosphate donor (Km 19 microM). Enzyme activity was maximal in the presence of 10 mM MgCl2, whereas it decreased in the presence of spermine, polylysine, quercetin, and NaCl (20-250 mM). CK-B seemed to have a monomeric structure of about 41 kDa; it underwent autophosphorylation and cross-reacted with polyclonal antibodies raised against recombinant alpha, but not beta, subunit of human type 2 casein kinase. It phosphorylated both serine and threonine residues of casein and phosvitin, utilizing ATP (Km 12 microM) but not GTP as a phosphate donor. Threonine was more affected in the phosphorylated phosvitin than in the partially dephosphorylated substrate. CK-B was active toward the synthetic peptide Ser-(Glu)5 and calmodulin (in the latter case, in the presence of polylysine), and it was activated by spermine, polylysine, MgCl2 (30 mM), and NaCl (20-400 mM). The activity of the enzymes was not affected by cAMP, or the heat-stable inhibitor of the cAMP-dependent protein kinase, or calcium.

Continuous flow immunosensor for atrazine detection.

The hapten atrazine was detected under continuous flow conditions using a micro-column which contained immobilized monoclonal antibodies (Ab) against atrazine and atrazine labeled with alkaline phosphatase (An*). The equilibrium of the antibody-hapten system, was achieved by a continuous flow of the tracer An* through the micro-column containing the immobilized antibodies. The activity of the tracer was monitored continuously, after the micro-column, by an amperometric detector using p-hydroquinone phosphate as substrate. When pulses of unlabeled atrazine (An) were added to the An* flowing continuously through the micro-column, An* bound to the antibody was displaced, with a consequent change of the detector signal. By this method atrazine concentrations in the range 9-180 micrograms/l were monitored under conditions of continuous operation. Since the equilibrium condition for the system Ab-An* was continuously restored by the flow of An* through the micro-column the regeneration of the antibody was not required.

The efficacy of two doses of omeprazole for short- and long-term peptic ulcer treatment in the elderly.

This study evaluated the efficacy, safety, and most suitable dose of omeprazole in short-term acute treatment (4 weeks) and maintenance treatment (6 months) of patients older than 60 years of age with endoscopically diagnosed gastric ulcer (GU) or duodenal ulcer (DU). This randomized, prospective study included 156 patients (67 GU and 89 DU; mean age, 74.8 and 72.3 years, respectively) who were randomized in the acute phase into two treatment groups: omeprazole 20 mg/d or 40 mg/d as a single morning dose for 4 weeks. The 6-month follow-up phase included 101 patients who were randomized to receive omeprazole 20 mg/d or 20 mg every other day. After 4 weeks of treatment, 94.0% of GU patients and 95.5% of DU patients showed complete ulcer scarring with no statistical differences between doses. At the end of the 6-month follow-up, 4.5% of GU patients and 8.8% of DU patients relapsed, with no statistical differences between groups. No clinically significant adverse events were recorded. In conclusion, omeprazole is a highly effective, well-tolerated, and safe drug for the short- and long-term treatment of GU and DU in the elderly. The dose of 20 mg/d for the acute phase and 20 mg on alternate days for maintenance therapy appears most appropriate for elderly patients with ulcers.

Detection of B-cell monoclonality in fine needle aspiration by PCR analysis.

Cytologic examination of fine-needle aspiration (FNA) sometimes fails to diagnose the malignant nature of B-cell proliferations. In this study we analyzed the Ig gene rearrangement of 49 FNA samples by polymerase chain reaction (PCR) in order to evaluate whether molecular analyses can improve the accuracy of FNA. Twenty-six patients had non-Hodgkin's lymphoma, 11 had reactive lymphoid diseases, 5 had chronic inflammation and 7 had carcinoma. A semi-nested PCR was performed using an oligoprimer specific for consensus sequences of the V regions (FR3A) and two oligoprimers derived from conserved sequences of the J regions (LJH and VLJH). Histologic examination always followed the molecular and cytologic analysis. The sensitivity of PCR and FNA morphological examination in detecting a neoplastic pattern was 92% and 78%, respectively. When samples were considered inadequate for cytologic examination, PCR always reached a diagnosis consistent with the histologic features. Our results demonstrate that PCR analysis of FNA specimens is a reliable and sensitive method capable of enhancing the diagnostic accuracy of cytologic examination.

Remission in hairy cell leukemia-variant following splenic radiotherapy alone.

The therapeutic approach to hairy cell leukemia (HCL) is in some instances still debated. A variant form of HCL (HCL-V) characterized by high white cell count, splenomegaly, hypercellular and aspirable bone marrow has been described; differential diagnosis often arises with some other B-cell disorders which also show circulating hairy or villous lymphocytes. Conventional treatment for HCL is often less effective in HCL-V. In this report we describe a case with features consistent with HCL-variant treated with splenic radiotherapy. We not only obtained an hematological response but also the near total disappearance of bone marrow infiltration, compatible with a clinical complete remission. Clinical and biological implications of this phenomenon are discussed on the basis of this unexpected therapeutic result, obtained with splenic radiotherapy alone.

Laboratory medicine in ulcer disease.

The role of laboratory medicine in ulcer disease is poorly defined. However there is increasing evidence of the clinical usefulness of some laboratory tests that investigate secretory functions and defensive properties of the stomach, gastrointestinal hormones and Helicobacter pylori infection. These tests may modify the clinical management of patients with peptic ulcer by identifying H. pylori positive subjects, patients with high acid output, patients who do not respond to antisecretory therapy, and patients with high gastrin levels in whom Zollinger-Ellison syndrome may be suspected. Here we review the clinical value of laboratory tests in ulcer disease, particularly as concerns the cost/benefit ratio. The relative merits of these tests are described giving an indication of their possible role in the diagnostic algorithm.

Role of serum fasting gastrin in screening for hypergastrinemic syndromes in duodenal ulcer disease.

Basal serum gastrin levels were measured in 237 patients with endoscopically confirmed duodenal ulcer and were higher than normal in 16 cases. Protein meal gastrin stimulation was performed on this group of 16 patients and on a control group of 48 patients with normal basal gastrin concentrations but high rates of either ulcer recurrence or of complications (e.g., bleeding or perforation); 21 patients from the two groups were also tested for serum gastrin inhibition with secretin. Four cases (25%) of antral G-cell hyperfunction were found in the first group, plus 1 case compatible with Zollinger-Ellison syndrome (6.2%). Only 1 case (2%) of antral G-cell hyperfunction was found among the 48 controls. These results suggest the clinical utility of routine basal gastrin measurement in screening for hypergastrinemic patients with duodenal ulcer disease.

Pepsinogen Group I radioimmunoassay and total serum pepsinogen colorimetric determination: a comparative study in normal subjects and in peptic ulcer patients.

Pepsinogens, proteolytic enzymes produced by peptic cells of the stomach and discharged into the gastric lumen as well as into the blood have been divided into two groups: PG-I, originating from chief cells, and PG-II, mainly from antrum peptic cells. Both total serum pepsinogen (s-Pg) and PG-I have been separately reported as being significantly increased in gastric (GU) and duodenal ulcer (DU) patients and related to maximal acid output. In order to ascertain the relationship between s-Pg measured by means of the colorimetric Uete method, and PG-I determined by RIA method, these were assayed in 72 control subjects, 35 GU and 95 DU patients. s-Pg was found to be significantly increased both in GU and DU patients in comparison with control subjects. Likewise PG-I was significantly enhanced in GU and DU patients as compared with controls. A significant direct correlation between s-Pg and PG-I was found in all the subjects studied (r = 0.732).

Actual role of pepsinogen group I in the study of upper gastrointestinal diseases.

The role of serum PG I in screening patients with chronic atrophic gastritis and gastric cancer, and in detecting peptic ulcer patients with high relapse risk, was ascertained in 276 subjects. Although not diagnostic per se, PG I was found to be under 20 micrograms/L in patients with chronic atrophic gastritis and in some gastric cancer or partially gastrectomized patients. In patients presenting with relapsing duodenal ulcer, PG I values were significantly higher than in the non-relapsing ones, but a satisfactory identification of all the duodenal ulcer patients with high relapse risk was not possible on this basis. Even the correlation between PG I and MAO was not accurate in every subject considered. These results suggest that the value of PG I is limited to assessing patients with upper gastrointestinal diseases in which a reduction of peptic secretion, and therefore of PG I in serum, is present.

Prevalence of Helicobacter pylori infection in patients with precancerous changes and gastric cancer.

Several papers suggested a role for H. pylori infection in gastric cancer. We evaluated the prevalence of H. pylori infection in an endoscopic population of patients with gastric precancerous conditions and lesions by studying biopsies from 252 patients and recording the presence and degree of H. pylori infection. Patients were subgrouped as follows: chronic non-atrophic gastritis (CG), chronic atrophic gastritis (CAG), intestinal metaplasia (IM), epithelial dysplasia (ED) and gastric cancer (K). As control populations, patients with duodenal ulcer (DU) and patients with no endoscopic and histologic damage (CO) were investigated. H. pylori infection rate increased with age, but became significantly lower (P < 0.001) with the progression of gastric mucosal damage: DU 85%, CG 72%, CAG 58%, particularly in the antral type (39%), IM 63% overall, ED 44% and K 35%. The density of colonization showed the same trend (P < 0.001). Of the K patients, only 36% were H. pylori positive in the adjacent mucosa. Anti-H. pylori antibodies (IgG, IgA and IgM) were also tested. A concordance in the diagnosis between histology and serology was obtained in 82% of the cases. In our experience, H. pylori infection correlates inversely with the presence of gastric precancerous changes and cancer. A cautious interpretation of the epidemiological data regarding H. pylori infection and gastric cancer is therefore, in our opinion, mandatory.