A novel dendrimeric peptide with antimicrobial properties: structure-function analysis of SB056

The novel antimicrobial peptide with a dimeric dendrimer scaffold, SB056, was empirically optimized by high-throughput screening. This procedure produced an intriguing primary sequence whose structure-function analysis is described here. The alternating pattern of hydrophilic and hydrophobic amino acids suggests the possibility that SB056 is a membrane-active peptide that forms amphiphilic β-strands in a lipid environment. Circular dichroism confirmed that the cationic SB056 folds as β-sheets in the presence of anionic vesicles. Lipid monolayer surface pressure experiments revealed unusual kinetics of monolayer penetration, which suggest lipid-induced aggregation as a membranolytic mechanism. NMR analyses of the linear monomer and the dendrimeric SB056 in water and in 30% trifluoroethanol, on the other hand, yielded essentially unstructured conformations, supporting the excellent solubility and storage properties of this compound. However, simulated annealing showed that many residues lie in the β-region of the Ramachandran plot, and molecular-dynamics simulations confirmed the propensity of this peptide to fold as a β-type conformation. The excellent solubility in water and the lipid-induced oligomerization characteristics of this peptide thus shed light on its mechanism of antimicrobial action, which may also be relevant for systems that can form toxic β-amyloid fibrils when in contact with cellular membranes. Functionally, SB056 showed high activity against Gram-negative bacteria and some limited activity against Gram-positive bacteria. Its potency against Gram-negative strains was comparable (on a molar basis) to that of colistin and polymyxin B, with an even broader spectrum of activity than numerous other reference compounds.

Susceptibility loci for polycystic ovary syndrome on chromosome 2p16.3, 2p21, and 9q33.3 in a cohort of Caucasian women

In a recent genome-wide association study investigating Han Chinese PCOS women 3 loci that are strongly associated with PCOS were identified on chromosome 2p16.3 (rs13405728), 2p21 (rs13429458), and 9q33.3 (rs2479106). The aim of the study was to investigate the impact of rs13405728, rs13429458, and rs2479106 variants on PCOS susceptibility in a Caucasian cohort of PCOS and control women. Metabolic, endocrine, and anthropometric measurements and oral glucose tolerance tests were performed in 545 PCOS and 317 control women. The rs13405728, rs13429458, and rs2479106 polymorphisms were genotyped. There was no significant difference in genotype frequencies of rs13405728 and rs13429458 variants between PCOS and controls. There was a trend towards an association of the rs2479106 variant with PCOS susceptibility (p=0.053). PCOS women with the rs2479106 GG genotype had significantly higher WHR than PCOS women carrying the AG and AA genotype (p=0.034 and p=0.020, respectively). Moreover, QChol/HDL and LDL levels were significantly higher in PCOS women carrying the rs2479106 GG genotype when compared to those carrying the AA genotype (p=0.024 and p=0.035, respectively). PCOS women carrying the G allele of rs13405728 had significantly higher AUCgluc, glucose-30 min, and AUCins levels than those carrying the AA genotype (p=0.039, p=0.047, and p=0.044, respectively). In PCOS women, rs13405728 genotypes are associated with glucose and insulin metabolism. Moreover, rs2479106 genotypes were associated with increased WHR levels and an adverse serum lipid profile. Further, we observed a trend towards decreased PCOS susceptibility within carriers of the rs2479106 G-allele. Further studies in large Caucasian PCOS cohorts are warranted to confirm our findings.

Isotope quantum effects on the water proton mean kinetic energy

A deep inelastic neutron scattering experiment, performed on D(2)O in the stable and metastable liquid phases, provides evidence for isotope quantum effects in the proton or deuteron single particle dynamics along the hydrogen bond. The deuteron mean kinetic energy extracted from the experimental data in the metastable supercooled phase (T = 276.15 K) exceeds the zero point energy and scales as sqrt[2] with that of protons in supercooled light water, at T = 269.15 K. The present data support the suggestion that even small changes in the short range environment of a deuteron or proton have a strong influence on its quantum behavior.

Fractal analysis in a systems biology approach to cancer

Cancer is a highly complex disease due to the disruption of tissue architecture. Thus, tissues, and not individual cells, are the proper level of observation for the study of carcinogenesis. This paradigm shift from a reductionist approach to a systems biology approach is long overdue. Indeed, cell phenotypes are emergent modes arising through collective non-linear interactions among different cellular and microenvironmental components, generally described by "phase space diagrams", where stable states (attractors) are embedded into a landscape model. Within this framework, cell states and cell transitions are generally conceived as mainly specified by gene-regulatory networks. However, the system's dynamics is not reducible to the integrated functioning of the genome-proteome network alone; the epithelia-stroma interacting system must be taken into consideration in order to give a more comprehensive picture. Given that cell shape represents the spatial geometric configuration acquired as a result of the integrated set of cellular and environmental cues, we posit that fractal-shape parameters represent "omics" descriptors of the epithelium-stroma system. Within this framework, function appears to follow form, and not the other way around.

High prevalence of latent tuberculosis infection in autoimmune disorders such as psoriasis and in chronic respiratory diseases, including lung cancer

The early diagnosis and treatment of individuals harboring M. tuberculosis is key to ensuring the effectiveness of health programs aimed at the elimination of tuberculosis (TB). Monitoring for TB also has other important health care implications for the related immune pathology caused by the chronic inflammatory response to M. tuberculosis. Moreover, the recent introduction of biologic therapies for the treatment of several immune-mediated inflammatory diseases has shown unexpected high frequencies of reactivation of latent TB. The present cross-sectional study is aimed at estimating the prevalence of latent tuberculosis infection (LTBI) in different groups of subjects, either undergoing a routine program of screening for TB or a clinical monitoring of autoimmune or lung disorders, by analyzing their immune response in vitro to a pool of different M. tuberculosis antigens through an IFN-gamma-release assay (IGRA). We consecutively tested 1,644 subjects including health care workers (931), healthy immigrants from different countries (93), patients with a diagnosis of psoriasis (405), patients with lung inflammatory disease (60) or lung neoplasia (32) and a group of HIV-1 infected Italian subjects (120). The prevalence of IGRAs positive responses among health care workers was 8.9 percent. In comparison, significantly higher frequencies were found in healthy immigrant subjects (33.3%), similar to those found in inflammatory broncho-pneumopathies (34.5%) or lung cancer (29.6%). Interestingly, an unexpected high prevalence was also found in patients affected by psoriasis (18.0%), while HIV-infected subjects had values comparable to those of health care workers (10.8%). An age cut-off was determined and applied for each group by receiver operating characteristic (ROC) curves in order to perform the statistical analysis among age-comparable groups. Multivariate analysis showed that the age and clinical conditions such as having a diagnosis of psoriasis or a lung inflammatory disease were independent risk factors for developing an IGRA positive response. This study highlights an unprecedented high prevalence of IGRA positive responses among patients affected by psoriasis and emphasizes the need for a preliminary assessment of LTBI before the administration of any biologic therapy based on cytokine antagonists such as anti-TNF-alpha. Moreover, screening for LTBI should be routinely performed in the presence of a chronic pulmonary disease.

Effect of vascular risk factors on increase in carotid and femoral intima-media thickness. Identification of a risk scale

BACKGROUND

The well established correlation between intima-media thickness (IMT) and the risk of cardiovascular and cerebrovascular events and death is usually measured in subjects with multiple vascular risk factors, which makes it difficult, after application of the usual analysis-of-variance linear combination of effects model, to establish whether each cardiovascular risk factor has, per se, an effect on IMT.

METHOD AND RESULTS

In this study we investigated five "pure" groups of patients (865), i.e. each presenting only one of the following risk factors: hypertension, obesity, overweight, smoking, hypercholesterolaemia and a control group of 37 healthy subjects. We measured, both as discrete and as continuous variables, the following indices: intima-media thickening of the common carotid artery (IMT(C)) and of the common femoral artery (IMT(F)) and the ankle-brachial index (ABI). Descriptive statistics were used to analyse the prevalence of pathological values for the three indices in the different groups. Subsequently the entire group of 902 subjects was included in a correlation analysis in which the Pearson correlation coefficient for each pair of variables was computed. In order to assign the risk factors a continuous ranking, and obtain a more general idea of the correlation structure, principal component analysis (PCA) was used. The scores obtained from PCA made it possible to build a scale of severity of the vascular risk factors considered. All the risk factors considered were demonstrated to strongly affect the studied indices. Overweight was shown to be the least important risk factor with regard to intima-media thickening, followed by smoking, hypercholesterolaemia, hypertension and finally obesity, which emerged as the greatest risk factor.

CONCLUSIONS

The strong correlation between the indices made it possible to compute a composite general score, which provides an univocal risk estimation at single-patient level. IMT(F) was demonstrated to be the most sensitive descriptor. The construction of this risk scale has implications for preventive treatment and the frequency of instrumental examinations, allowing clear quantitative definition of the extent of the damage.

Terrestrial gamma-ray flashes as powerful particle accelerators

Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and γ rays lasting a few milliseconds or less. We present in this Letter new TGF timing and spectral data based on the observations of the Italian Space Agency AGILE satellite. We determine that the TGF emission above 10 MeV has a significant power-law spectral component reaching energies up to 100 MeV. These results challenge TGF theoretical models based on runaway electron acceleration. The TGF discharge electric field accelerates particles over the large distances for which maximal voltages of hundreds of megavolts can be established. The combination of huge potentials and large electric fields in TGFs can efficiently accelerate particles in large numbers, and we reconsider here the photon spectrum and the neutron production by photonuclear reactions in the atmosphere.

Screening of Helicobacter pylori infection after gastrectomy for cancer or peptic ulcer: results of a cohort study

BACKGROUND

Gastric cancer commonly follows a long-standing inflammation, mainly due to Helicobacter pylori (HP) infection. After resection, the stump develops precancerous alterations.

DESIGN

Prospective study of patients undergoing endoscopy from April 1, 2000, through March 31, 2006.

SETTING

University departments of Surgery and Experimental Medicine and Pathology.

PATIENTS

One hundred eighty-seven patients receiving upper gastrointestinal tract endoscopy many years after surgery for duodenal ulcer or gastric cancer. Ten to 12 postoperative endoscopic biopsy samples were taken from the remnant stomach.

MAIN OUTCOME MEASURE

The risk of gastric cancer precursor lesions associated with HP infection.

RESULTS

The gastric cancer precursor lesions were more common in the entire HP-positive population (odds ratio [OR], 2.37; 95% confidence interval [CI], 1.25-4.49; P = .007). However, HP-positive patients undergoing resection for cancer had a higher risk of the precursor lesions compared with HP-negative patients in the same diagnostic group (OR, 4.20; 95% CI, 1.10-15.96) and all patients undergoing resection for duodenal ulcer (OR, 1.59; 95% CI, 0.44-5.73).

CONCLUSION

The results of this investigation support the role of HP in gastric carcinogenesis and suggest that the HP eradication therapy might prevent the development of metachronous gastric cancer after gastric resection.

Endoluminal metastasis of colon cancer to the urinary bladder via the ureter: report of a case

A 67-year-old woman was admitted for intermittent gross hematuria. Her medical history included a right colectomy for cancer of the ascending colon and removal of metastatic nodes adjacent to the right internal iliac vessels, respectively at 63 and 65 years of age. Cystoscopy detected a semi-pedunculated, nonpapillary (3.5-4 cm diameter) tumor situated above the right ureteral orifice. The histological evaluation of the resected specimen revealed metastatic colonic adenocarcinoma. The history and pathological findings were consistent with a mechanism of endoluminal implantation of adenocarcinoma of the large bowel to the bladder via the right ureter.

Gamma-ray localization of terrestrial gamma-ray flashes

Terrestrial gamma-ray flashes (TGFs) are very short bursts of high-energy photons and electrons originating in Earth's atmosphere. We present here a localization study of TGFs carried out at gamma-ray energies above 20 MeV based on an innovative event selection method. We use the AGILE satellite Silicon Tracker data that for the first time have been correlated with TGFs detected by the AGILE Mini-Calorimeter. We detect 8 TGFs with gamma-ray photons of energies above 20 MeV localized by the AGILE gamma-ray imager with an accuracy of ∼5-10° at 50 MeV. Remarkably, all TGF-associated gamma rays are compatible with a terrestrial production site closer to the subsatellite point than 400 km. Considering that our gamma rays reach the AGILE satellite at 540 km altitude with limited scattering or attenuation, our measurements provide the first precise direct localization of TGFs from space.

Synthesis, characterization, antimicrobial activity and LPS-interaction properties of SB041, a novel dendrimeric peptide with antimicrobial properties

Multimeric peptides offer several advantages with respect to their monomeric counterparts, as increased activity and greater stability to peptidases and proteases. SB041 is a novel antimicrobial peptide with dendrimeric structure; it is a tetramer of pyrEKKIRVRLSA linked by a lysine core, with an amino valeric acid chain. Here, we report on its synthesis, NMR characterization, antimicrobial activity, and LPS-interaction properties. The peptide was especially active against Gram-negative strains, with a potency comparable (on molar basis) to that of lipopeptides colistin and polymixin B, but it also displayed some activity against selected Gram-positive strains. Following these indications, we investigated the efficacy of SB041 in binding Escherichia coli and Pseudomonas aeruginosa LPS in vitro and counteracting its biological effects in RAW-Blue cells, derived from RAW 264.7 macrophages. SB041 strongly bound purified LPS, especially that of E. coli, as proved by fluorescent displacement assay, and readily penetrated into LPS monolayers. However, the killing activity of SB041 against E. coli was not inhibited by increasing concentrations of LPS added to the medium. Checking the SB041 effect on LPS-induced activation of pattern recognition receptors (PRRs) in Raw-Blue cells revealed that while the peptide gave a statistically significant decrease in PRRs stimulation when RAW-Blue cells were challenged with P. aeruginosa LPS, the same was not seen when E. coli LPS was used to activate innate immune defense-like responses. Thus, as previously seen for other antimicrobial peptides, also for SB041 binding to LPS did not translate necessarily into LPS-neutralizing activity, suggesting that SB041-LPS interactions must be of complex nature.

The galanin receptor 2/3 agonist Gal2-11 protects the SN56 cells against beta-amyloid 25-35 toxicity

The neuropeptide galanin is a modulator of cholinergic function and may play a role in A beta peptide-induced degeneration of cholinergic forebrain neurons. We have studied the effect of galanin and its galanin receptor subtype 2/3 agonist Gal2-11on toxicity induced by freshly-prepared beta-amyloid(25-35) in the cholinergic cell line SN56. Both nuclear fragmentation and caspase-3 expression were analysed. beta-amyloid(25-35)-exposure induced a significant increase in caspase-3 mRNA expression after 30, 60, 90 or 150 min of beta-amyloid(25-35) exposure. These effects were abolished in the presence of Gal2-11 (10 nM). Similarly, beta-amyloid(25-35)-induced nuclear fragmentation was prevented by the galanin agonist at all time points studied. These findings indicate that the galanin 2/3 agonist Gal2-11 protects SN56 cholinergic cells from beta-amyloid(25-35)-induced cell death and that this action is mediated by an early reduction of caspase-3 expression.

An uncommon case of systemic Mucormycosis associated with spinal cord infarction in a recently diagnosed diabetic

Mucormycosis is a relatively rare, opportunistic, invasive infection caused by various members of the Phycomycetes class [from Greek phyko- seaweed; having a plant body], an extensive taxonomy introduced in 1956 to enlarge the class of Zygomycetes. These filamentous fungi have a worldwide distribution and are capable of rapid growth and thermotolerance of human body temperature. Infection typically occurs in seriously compromised patients (i.e. diabetic ketoacidosis, hematologic malignancies, immunosuppressive disorders, end-stage renal disease, solid-organ or bone-marrow transplantation) and can be acute or fulminant, as well as indolent and chronic. In this paper we describe a case of cutaneous mucormycosis that occurred in a 54-year-old diabetic woman and evolved into a disseminated form, leading to an uncommon spinal cord infarction and consequent paraparesis. Our case suggests the importance of suspecting a mucormycosis infection in patients with decompensated diabetes mellitus, even without ketoacidosis.

Ozone as u-shaped dose responses molecules (hormetins)

Redox environment involves a broad network of pro-oxidant and antioxidant components. Health benefit or damage can be induced as a consequence of an adaptive cellular stress response. A consequence of hormetic amplification is an increase in the homeodynamic space of a living system in terms of an increased defense capacity and a reduced load of damaged macromolecules. Ozone, when used at appropriate doses, promotes the formation of reactive oxygen species and lipid peroxides allows them to become late and long-lasting messengers. Healthy aging may be achieved by hormesis through mild and periodic, but not severe or chronic, physical and mental challenges, and by the use of nutritional hormesis incorporating mild stress-inducing molecules called hormetins. The paradoxical concept that ozone eventually induces an antioxidant response capable of reversing a chronic oxidative stress is common in the animal and vegetal kingdom; it is already supported by findings of an increased level of antioxidant enzymes during ozone therapy. Those facts can include ozone as a hormetin. The established scientific foundations of hormesis are ready to pave the way for new and effective approaches in redox-related disease research and intervention; ozone therapy can be a good candidate.

Peptide-derivatized dendrimers inhibit human cytomegalovirus infection by blocking virus binding to cell surface heparan sulfate

Dendrimers are hyperbranched synthetic well-defined molecules with a number of potential applications, especially in relation to the need for new antiviral agents. One subclass of dendrimers are peptide-derivatized dendrimers which consist of a peptidyl branching core and covalently attached surface peptide functional units. Few studies have addressed the potential uses of peptide dendrimers as direct-acting antiviral agents. Here, we report on the ability of two peptide dendrimers, SB105 and SB105_A10, to directly and almost completely inhibit human cytomegalovirus (HCMV) replication in both primary fibroblasts and endothelial cells; the agents were also found to inhibit murine CMV replication, whereas they were not able to inhibit adenovirus or vesicular stomatitis virus. The peptide dendrimers prevented adsorption of the HCMV to cells at 4 degrees C, whereas SB104, a dendrimer with a different amino acid sequence within the functional group and minimal anticytomegaloviral activity, was ineffective in blocking HCMV attachment. In effect, SB105_A10 bound to human cells through an interaction with cell surface heparan sulfate and thereby blocked virion attachment to target cells. These results indicate that the SB105 and SB105_A10 dendrimers could provide a useful starting point for the development of novel molecules to block HCMV infection.

Antimicrobial peptides: the LPS connection

An expanding body of evidence is rendering manifest that many cationic antimicrobial peptides are endowed with different properties and activities, well beyond their direct action on microbes. One of the most interesting and potentially important research avenue on the alternative use of antimicrobial peptides grounds on their affinity toward lipopolysaccharide (LPS), the endotoxin, responsible for the systemic inflammatory response syndrome (SIRS) and related, often fatal, disorders that can follow Gram-negative infections. Indeed, not only do several antimicrobial peptides, such as cathelicidins, display an ability to strongly bind LPS and break its aggregates, but they have also been demonstrated to suppress LPS-induced pro-inflammatory responses in vitro and to protect from sepsis in animal models. Although many aspects still need to be carefully evaluated - some of which are highlighted here - a mix of antimicrobial, LPS-sequestering/neutralization, and immunomodulatory features make cationic peptides, and especially synthetic or semi-synthetic amphiphilic compounds built on their scheme, attractive candidates for novel drugs to be administered in antisepsis therapies. These therapies will probably hinge either on compounds able to intervene at multiple points in the sepsis cascade or on the combination of two or more immunomodulators.

Association of hypovitaminosis D with metabolic disturbances in polycystic ovary syndrome

OBJECTIVES

Women with polycystic ovary syndrome (PCOS) frequently suffer from metabolic disturbances, in particular from insulin resistance. Accumulating evidence suggests that vitamin D deficiency may contribute to the development of the metabolic syndrome (MS). Hence, the aim of our study was to investigate the association of 25(OH)D levels and the components of the MS in PCOS women.

METHODS

25(OH)D levels were measured by means of ELISA in 206 women affected by PCOS. Metabolic, endocrine, and anthropometric measurements and oral glucose tolerance tests were performed.

RESULTS

The prevalence of insufficient 25(OH)D levels (<30 ng/ml) was 72.8% in women with PCOS. PCOS women with the MS had lower 25(OH)D levels than PCOS women without these features (17.3 vs 25.8 ng/ml respectively; P<0.05). In multivariate regression analysis including 25(OH)D, season, body mass index (BMI), and age, 25(OH)D and BMI were independent predictors of homeostatic model assessment-insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI; P<0.05 for all). In binary logistic regression analyses, 25(OH)D (OR 0.86, P=0.019) and BMI (OR 1.28, P<0.001) were independent predictors of the MS in PCOS women. We found significantly negative correlations of 25(OH)D levels with BMI, waist circumference, waist-to-hip ratio, systolic and diastolic blood pressure, fasting and stimulated glucose, area under the glucose response curve, fasting insulin, HOMA-IR, HOMA-beta, triglycerides, and quotient total cholesterol/high-density lipoprotein (HDL) and positive correlations of 25(OH)D levels with QUICKI and HDL (P<0.05 for all).

CONCLUSION

We demonstrate that low 25(OH)D levels are associated with features of the MS in PCOS women. Large intervention trials are warranted to evaluate the effect of vitamin D supplementation on metabolic disturbances in PCOS women.

Ultra-low background measurements of decayed aerosol filters

Aerosol samples collected on filter media were analyzed using HPGe detectors employing varying background-reduction techniques in order to experimentally evaluate the opportunity to apply ultra-low background measurement methods to samples collected, for instance, by the Comprehensive Test Ban Treaty International Monitoring System (IMS). In this way, realistic estimates of the impact of low-background methodology on the sensitivity obtained in systems such as the IMS were assessed. The current detectability requirement of stations in the IMS is 30 μBq/m³ of air for ¹⁴⁰Ba, which would imply ~10⁶ fissions per daily sample. Importantly, this is for a fresh aerosol filter. One week of decay reduces the intrinsic background from radon daughters in the sample allowing much higher sensitivity measurement of relevant isotopes, including ¹³¹I. An experiment was conducted in which decayed filter samples were measured at a variety of underground locations using Ultra-Low Background (ULB) gamma spectroscopy technology. The impacts of the decay and ULB are discussed.

A Rare Case of Hematuria from Colonic Adenocarcinoma Spreading to the Bladder via the Stented Ureter

Background

The direct extension of advanced tumors from adjacent organs to the bladder is not uncommon. Secondary bladder involvement through hematogenous and/or lymphatic metastases and implant of cells by tumors involving higher urinary tract via the ureter are rare. Therefore, the histological resemblance between primary bladder adenocarcinoma and colorectal adenocarcinoma can be a dilemma for pathologists.

Methods

A 67-year-old female underwent total right hemicolectomy for ascending colon adenocarcinoma. After a 20-month follow-up the lesion was removed (which was histopathologically similar to the previous colon cancer) and the patient underwent ureteral stenting because of a mass in the right internal iliac nodes with homolateral hydronephrosis. Subsequently intermittent gross hematuria urged on performing cystoscopy detecting a non-papillary mass situated above the right ureteral orifice, previously revealed on ultrasonography and CT scan.

Results

A TURBT was performed. Histopathologically the mass, partially covered by intact urothelium, consisted of tubular and pseudoglandular structures intermixed with solid foci of mucin-producing signet-ring-cells-type adenocarcinoma, very similar to the original colon cancer. The tumor base was healthy. Immunohistochemically stains for cytokeratin 7 (CK7) and cytokeratin 20 (CK20) presented multifocal positivity, suggesting the colorectal origin of the neoplasm.

Conclusions

In order to optimize the therapeutic options, it is important to distinguish the primary disease of the bladder from other causes of hematuria, and achieve a correct differentiation between primary enteric-type adenocarcinoma of the bladder and secondary colorectal adenocarcinoma involving the bladder, these entities being morphologically indistinguishable. Therefore, in patients with history of colonic adenocarcinoma, the presence of a subsequent bladder tumor should be considered as an eventuality of a secondary disease.

Serum cytokines and bioumoral immunological characterization of psoriatic patients in long term etanercept treatment

The purpose of this study is to evaluate blood cytokines and immunological parameters in psoriatic patients during long-term treatment with Etanercept. Forty-five subjects of both sexes affected by psoriasis with or without arthritis entered the study and were treated with Etanercept according to international standard protocols. Biochemical blood analysis was carried out at baseline and during follow-up every second month. In particular, the following parameters were kept under control: antinuclear antibodies, anti-nDNA antibodies, anti-histone antibodies, blood cell count, circulating lymphocyte subtypes (CD3, CD4, CD8, CD16, CD19) and IgE. Cytokine profiles (IL-1-alpha, IL-1-beta, IL-6, IL-8, IL-10, IL-12, INF, TNF-alpha) were also evaluated in blood samples during the treatment up to 1 year of follow-up. A significant decrease in PASI score (p < 0.01) and in several cytokine levels was observed, particularly in IL-1, IL-6, IFN-gamma (p < 0.01) and to a lesser extent in TNF-alpha (p < 0.05). No statistically significant changes were recorded after 1 year of follow-up in blood immunological parameters, in particular in ANA titre, CD4/CD8 ratio, IgE levels, CD16, CD19 and eosinophils count. In conclusion, long-term treatment with Etanercept leads not only to a significant improvement in PASI score, but also to significant changes (reduction) in several proinflammatory and modulatory cytokines involved in the pathogenesis of the disease; on the other hand, there are no effects on immunological or bioumoral parameters showing that etanercept modulates rather than suppresses the physiological responses during psoriasis treatment.

Antimicrobial peptides: natural templates for synthetic membrane-active compounds

The innate immunity of multicellular organisms relies in large part on the action of antimicrobial peptides (AMPs) to resist microbial invasion. Crafted by evolution into an extremely diversified array of sequences and folds, AMPs do share a common amphiphilic 3-D arrangement. This feature is directly linked with a common mechanism of action that predominantly (although not exclusively) develops upon interaction of peptides with cell membranes of target cells. This minireview reports on current understanding of the modes of interaction of AMPs with biological and model membranes, especially focusing on recent insights into the folding and oligomerization requirements of peptides to bind and insert into lipid membranes and exert their antibiotic effects. Given the potential of AMPs to be developed into a new class of anti-infective agents, emphasis is placed on how the information on peptide-membrane interactions could direct the design and selection of improved biomimetic synthetic peptides with antibiotic properties.

Isolated generalised anhidrosis induced by postganglionic sympathetic skin nerve fibre degeneration: an incomplete Ross syndrome?

Ross syndrome is characterised by tonic pupil, areflexia and anhidrosis, and the underlying lesion affects postganglionic skin sympathetic nerve fibres. We describe a 51-year-old man who had complained of anhidrosis since adolescence, at which time this problem was limited to the lower arms. The thermoregulatory sweating test disclosed generalised anhidrosis (GA) except for two small skin areas that were located in the right palm and left neck. Immunofluorescence analysis disclosed no cholinergic sudomotor fibres around the sweat glands of non-sweating skin areas, which were evident although sparse and deranged in the sweating site. In our patient, GA was induced by degeneration of postganglionic sympathetic skin nerve fibres, as found in Ross syndrome, although his clinical picture was incomplete as it lacked tonic pupil and areflexia. Isolated GA induced by degeneration of postganglionic sympathetic nerve fibers, directly evaluated by skin biopsy, has not previously been described.

Photoionization cross section of Xe+ ion in the pure 5p5 2P3/2 ground level

Coupling an ion trap with synchrotron radiation is shown here to be a powerful approach to measure photoionization cross sections on ionic species relaxed in their ground state. The photoionization efficiency curve of Xe+ ions stored in a Fourier transform ion cyclotron resonance ion trap was recorded at ELETTRA in the 20-23 eV photon energy range. Absolute cross sections were derived by comparison of the photoionization yield of Xe+ with measurements from the ASTRID merged-beam experiment. Multiconfiguration Dirac-Fock calculations were performed for the interpretation of these new data.

Company profile: Spider stories

SpiderBiotech is a biotech company that has carried out extensive research and development on peptide-based anti-infectives, with five people involved in R&D activities and a strong network of industrial and academic partners experienced in the field of anti-infectives. SpiderBiotech has also created a proprietary library of bioactive peptides and lipopeptides (both linear and dendrimeric) active against bacterial and viral infections. At the moment they have two ongoing projects: the most advanced is focused on the development of a panel of peptide based antibiotics. The second project is related to novel antiviral drugs to treat acyclovir resistant Herpes virus infections.

Electronic state spectroscopy of c-C5F8 explored by photoabsorption, electron impact, photoelectron spectroscopies and ab initio calculations

The electronic transitions and resonance-enhanced vibrational excitations of octafluorocyclopentene (c-C5F8) have been investigated using high-resolution photoabsorption spectroscopy in the energy range 6-11 eV. In addition, the high-resolution electron energy loss spectrum (HREELS) was recorded under the electric dipolar excitation conditions (100 eV incident energy, approximately 0 degrees scattering angle) over the 5-14 eV energy loss range. A He(I) photoelectron spectrum (PES) has also been recorded between 11 and 20 eV, allowing us to derive a more precise value of (11.288 +/- 0.002) eV for the ground neutral state adiabatic ionization energy. All spectra presented in this paper represent the first and highest resolution data yet reported for octafluorocyclopentene. Ab initio calculations have been performed for helping in the assignment of the spectral bands for both neutral excited states and ionic states.

Atmospheric pressure photoionization mass spectrometry of oligodeoxyribonucleotides

Small oligonucleotides (di- and trimers) were investigated by atmospheric pressure photoionization (APPI) with focus on the fragmentation mechanisms. The fragmentation patterns of these biomolecular ions have been monitored under dopant-assisted photoionization (DA-APPI) conditions. Our results reveal new aspects of the gas- phase chemistry of ions formed from such biomolecules. They illustrate that the reaction between low-energy electrons released from photoionization processes and di- and trinucleotides lies in dissociative electron attachment processes leading to phosphodiester bond cleavages and to the formation of numerous fragments in the ion source. The conditions of DA-APPI, which involve protic solvents and atmospheric pressure conditions, seem to be relevant for the study of radiation damages to biological molecules.

Age-dependent impairment of hippocampal neurogenesis in chronic cerebral hypoperfusion

Acute ischaemic brain damages, including both strokes and local ischaemia, are powerful stimulators of neurogenesis in the dentate gyrus of the hippocampus in adult rats and mice. As no data are available in chronic cerebral hypoperfusion, we investigated neurogenesis in rats after bilateral chronic occlusion of the carotid arteries (2VO). 2VO was performed in 3- and 12-month-old rats. Proliferation was investigated by bromodeoxyuridine uptake and MCM2 nuclear immunoreactivity, neurogenesis by counting doublecortin-IR cells in the subgranular area of the dentate gyrus of the hippocampus. We found increased proliferation and neurogenesis in the subgranular area of the dentate gyrus of the hippocampus in adult (3-month-old) rats 8 days after 2VO. This capability is lost in middle-aged (12-month-old) rats. Our data suggest that 2VO ligation can be a useful model for studying neurogenesis in experimental conditions mimicking long-lasting human pathologies, and also in the exploration of the uncertain relation between chronic brain hypoperfusion and age-related changes of cognitive function.

Reduction of cell proliferation induced by PD166866: an inhibitor of the basic fibroblast growth factor

Cell proliferation control plays a key role in tumor development. The basic Fibroblast Growth Factor (bFGF), as well as other growth factors, is involved in several pathologies characterized by dysregulation of cell proliferation. In the present work the effects of PD166866, a very potent and selective tyrosine kinase inhibitor were evaluated. Cultured murine fibroblasts (the cell line 3T6) were used to assess the FGFR-1 inhibition mediated by PD166866. Evaluation of cell viability and molecular biology techniques were adopted. PD166866 controls negatively the bFGF/FGFR-1 system thus promoting a significant reduction of cell proliferation and loss of viability in 3T6 cells. The drug possibly controls proliferation via induction of apoptosis as evidenced by a relevant chromatin degradation.

CONCLUSION

This study demonstrated that PD166866 might be used in the control of fibrotic proliferative diseases, as well as in other tumor pathologies.

Mesenteric fibromatosis. Case report

Deep fibromatosis is a rare locally aggressive but not metastasizing proliferation. Intra-abdominal fibromatosis (IAF) occurs either in association with Gardner's syndrome or as a sporadic event and presents in most cases differential diagnostic problems with myofibroblastic or fibroblastic tumors, characterized by a more aggressive biological behaviour such as gastrointestinal stromal tumors (GISTs). In absence of loco-regional and/or distant metastasis differential diagnosis may be difficult and represents a topical issue, since it influences treatment choice. We describe the case of a patient with sporadic IAF in which the tumor locally involved the mesentery and presented no loco-regional and distant spread. On histology, some morphological features of the neoplasm were in common with a GIST. Definitive diagnosis was made, postoperatively, on the basis of immunohistochemical findings.

Atomic force microscopy evaluation of the effects of a novel antimicrobial multimeric peptide on Pseudomonas aeruginosa

In this article we evaluated by atomic force microscopy (AFM) the effects of the (novel) tetrabranched antimicrobial peptide SB006 on morphology and mechanical properties of the gram-negative bacterium Pseudomonas aeruginosa. AFM imaging showed that SB006 causes the appearance of significant fragmentariness in the bacterial membrane and a severe volume decrease. Quantitative evaluation of the degree of fragmentariness was allowed by a new ad hoc image analysis procedure. The rigidity of the treated and untreated bacteria was measured through AFM tip nanoindentation measurements, and no differences registered. These results support the membrane interaction hypothesis, according to which SB006 targets the bacterial membranes and disrupts their permeability (allowing the leakage of cytoplasmic material and the subsequent shrinkage), but it does not affect the bacterium wall, which determines its rigidity.