Micro-ornamentation patterns in different areas of the epidermis in the gecko Tarentola mauritanica reflect variations in the accumulation of corneous material in Oberhautchen cells

Micro-ornamentations characterize the surface of scales in lepidosaurians and are summarized in four main patterns, i.e., spinulated, lamellated, lamellate-dentate, and honeycomb, although variations of these patterns are present in different species. Although geckos are known to possess a spinulated pattern derived from the Oberhautchen layer, also other pattern variations of the spinulated micro-ornamentation are present such as those indicated as dendritic ramification, corneous belts, and small bare patches. The present study mainly describes the variation of micro-ornamentations present in scales of different skin regions in the Mediterranean gecko Tarentula mauritanica using scannig and transmission electron microscopy. The study reports that the accumulation of corneous material in Oberhautchen cells is not homogenous in different areas of body scales and, when mature, this process gives rise to different sculpturing on the epidermal surface generating not only spinulae but also transitional zones leading to the other main patterns. It is hypothesized that spinulae formation derives from the vertical and lateral symmetric growth of tubercolate, non-overlapped scales of geckos. Sparse areas also result smooth or with serpentine-ridges likely revealing the beta-layer located underneath and merged with the Oberhautchen. The eco-functional role of this variable micro-ornamentation in the skin of lizards however remains largely speculative.

One year of surgical mask testing at the University of Bologna labs: Lessons learned from data analysis

The outbreak of SARS-CoV-2 pandemic highlighted the worldwide lack of surgical masks and personal protective equipment, which represent the main defense available against respiratory diseases as COVID-19. At the time, masks shortage was dramatic in Italy, the first European country seriously hit by the pandemic: aiming to address the emergency and to support the Italian industrial reconversion to the production of surgical masks, a multidisciplinary team of the University of Bologna organized a laboratory to test surgical masks according to European regulations. The group, driven by the expertise of chemical engineers, microbiologists, and occupational physicians, set-up the test lines to perform all the functional tests required. The laboratory started its activity on late March 2020, and as of the end of December of the same year 435 surgical mask prototypes were tested, with only 42 masks compliant to the European standard. From the analysis of the materials used, as well as of the production methods, it was found that a compliant surgical mask is most likely composed of three layers, a central meltblown filtration layer and two external spunbond comfort layers. An increase in the material thickness (grammage), or in the number of layers, does not improve the filtration efficiency, but leads to poor breathability, indicating that filtration depends not only on pure size exclusion, but other mechanisms are taking place (driven by electrostatic charge). The study critically reviewed the European standard procedures, identifying the weak aspects; among the others, the control of aerosol droplet size during the bacterial filtration test results to be crucial, since it can change the classification of a mask when its performance lies near to the limiting values of 95 or 98%.

AB1407 TELERHEUMATOLOGY AND WORKING VISIT: INITIAL MONOCENTRIC EXPERIENCE ON USE OF TELEVISIT IN THE REGULAR FOLLOW-UP

Background

The COVID-19 pandemic shifted most healthcare to remote delivery methods (telehealth technologies including clinical video televisit) to protect patients, clinicians, and hospital staff. Telerheumatology visits were found to be noninferior to in-person visits and are often more time and cost effective for patients.1

Objectives

Description of an initial integration of video televisit in regular follow-up.

Methods

In cooperation with the ALTEMS Operational Telemedicine Observatory, we built a procedural manual for televisit, whose phases were as much as possible similar to the usual visit scenario. Patients in remission or in mild disease activity at the time of enrolling visit were involved. Clinical characteristics, treatments and televisits’ features were considered for all patients (Table 1). Patient overall satisfaction was evaluated (rating 1 to 5).

Table 1.Patients (n.)74M/F27/47Age (y) median46.2±13.5RA n. (%)19 (25.6)PsA n. (%)21 (28.3)SpA (%)13 (17.5)CTD n. (%)8 (10,4)Vasculitis n. (%)7 (9.4)Other n. (%)6 (8.1)b or tsDMARDs n. (%)20 (62.5)Televisits n.86Mean duration (min.)17±3.5Satisfaction (1-5)4.68Device (PC/smartphone) %62.5/37.5Distance saved, mean (km)77,5Time travel saved, mean (min.)66CO2 saved (kg)866.71€ saved (per patient)44,37Working visit n. (%)5 (15.6)

Results

86 televisits were performed in 74 consecutive patients, with a mean age of 46.2 ± 13.5 years, diagnosed with the most common rheumatic diseases and on chronic immunosuppressive therapy (c-b-ts DMARDs mono or combination therapy). In 5 cases, in-person visit after televisit was required. the average duration of the televisit was 17 ± 3.5 minutes and the average overall satisfaction was 4.68 / 5. The average distance saved (round trip) was 77,5 km, equal to an avoided travel time of 66 minutes and with a total reduction in CO2 production of approximately 866 kg. 5 patients performed video visit from workplace, de facto inventing the “working visit”.

Conclusion

Telemedicine is going to become an essential element of clinical practice in rheumatology,2 especially for active, young, and working patients, helping to minimize the overall impact of the disease on QoL, as far as they are properly selected for clinical characteristics and informatic skills. The possibility to attend to televisit from the workplace will reduce the lost working-hours and the need of travel, thus acquiring undoubted social utility. In the near future, the use of televisit should be also extended to vulnerable patients lacking basic informatic resources, with the help of care-givers or dedicated territorial services.

References

[1]Matsumoto R, Barton JL. Curr Opin Rheum 2021 May; 1;33(3):262-269. doi:0.1097/BOR.0000000000000790.

[2]https://www.salute.gov.it/imgs/C_17_pubblicazioni_2129_allegato.pdf

ALTEMS = Alta Scuola di Economia e Management dei Sistemi Sanitari

Disclosure of Interests

None declared

Phenolic-rich extracts from acerola, cashew apple and mango by-products cause diverse inhibitory effects and cell damages on enterotoxigenic Escherichia coli

This study aimed to evaluate the inhibitory effects of phenolic-rich extracts from acerola (Malpighia emarginata D.C., PEA), cashew apple (Anacardium occidentale L., PEC) and mango (Mangifera indica L., PEM) by-products on distinct enterotoxigenic Escherichia coli (ETEC) strains. The capability of PEA and PEC of impairing various physiological functions of ETEC strains was investigated with multiparametric flow cytometry. Procyanidin B₂ , myricetin and p-coumaric acid were the major phenolic compounds in PEA, PEC and PEM, respectively. PEA and PEC had lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) (MIC: 31·25 mg ml^-1 ; MBC: 62·5 mg ml^-1 ) on ETEC strains than PEM (MIC and MIC: >1000 mg ml^-1 ). PEA and PEC (15·6, 31·2, 62·5 mg ml^-1 ) caused viable count reductions (P < 0·05) on ETEC strains after 24 h of exposure, notably the ≥3 log reductions caused by 62·5 mg ml^-1 . The 24 h exposure of ETEC strains to PEA and PEC (31·2, 62·5 mg ml^-1 ) led to high sizes of cell subpopulations with concomitant impairments in cell membrane polarization and permeability, as well as in enzymatic, respiratory and efflux activities. PEA and PEC are effective in inhibiting ETEC through a multi-target action mode with disturbance in different physiological functions.

Probiotic properties of yeasts isolated from Brazilian fermented table olives

AIMS

To investigate the probiotic potential of yeasts isolated from naturally fermented Brazilian table olives.

METHODS AND RESULTS

Eighteen yeast strains were tested in terms of: safety; survival of gastrointestinal and digestion conditions; antimicrobial activity; cellular hydrophobicity; autoaggregation ability and adhesion to epithelial cells; coaggregation and inhibition of pathogenic bacteria adhesion. Six yeasts showed favourable results for all probiotic attributes: Saccharomyces cerevisiae CCMA 1746, Pichia guilliermondii CCMA 1753, Candida orthopsilosis CCMA 1748, Candida tropicalis CCMA 1751, Meyerozyma caribbica CCMA 1758 and Debaryomyces hansenii CCMA 1761. These yeasts demonstrated resistance to 37°C, pH 2·0 and bile salts, and survived in vitro digestion (≥10⁶  CFU per ml). Furthermore, the yeasts exhibited a hydrophobic cell surface (42·5-92·2%), autoaggregation capacity (41·0-91·0%) and adhesion to Caco-2 (62·0-82·8%) and HT-29 (57·6-87·3%) epithelial cell lines. Also, the strains showed antimicrobial activity against Salmonella Enteritidis as well as the ability to coaggregate and reduce the adhesion of this pathogen to intestinal cells.

CONCLUSIONS

Autochthonous yeasts from naturally fermented Brazilian table olives have probiotic properties, with potential for development of new probiotic food products.

SIGNIFICANCE AND IMPACT OF STUDY

These data are important and contribute to the knowledge of new potential probiotic yeasts capable of surviving gastrointestinal tract conditions and inhibiting pathogenic bacteria.

Acerola (Malpighia glabra L.) and guava (Psidium guayaba L.) industrial processing by-products stimulate probiotic Lactobacillus and Bifidobacterium growth and induce beneficial changes in colonic microbiota

AIMS

This study evaluated whether by-products from industrial processing of acerola (Malpighia glabra L.; AB) and guava (Psidium guajava L.; GB) fruit may stimulate the growth and metabolism of probiotic Lactobacillus and Bifidobacterium and induce changes in human colonic microbiota.

METHODS AND RESULTS

The ability of non-digested and digested AB or GB to stimulate the growth ad metabolism of Lactobacillus acidophilus LA-05, Lactobacillus casei L-26 and Bifidobacterium animalis subsp. lactis BB-12 was evaluated. Changes in populations of distinct bacterial groups of human colonic microbiota induced by digested AB and GB were evaluated using an in vitro colonic fermentation system. Non-digested and digested AB and GB favoured probiotic growth. No difference among counts of probiotics in media with glucose, fructooligosaccharides and non-digested and digested AB and GB was found during a 48-h cultivation. Cultivation of probiotics in media with non-digested and digested AB and GB resulted in decreased pH, increased organic acid production and sugar consumption over time. Digested AB and GB caused overall beneficial changes in abundance of Bifidobacterium spp., Lactobacillus-Enterococcus, Eubacterium rectall-Clostridium coccoides and Bacteroides-Provotella populations, besides to decrease the pH and increase the short-chain fatty acid production during a 24-h in vitro colonic fermentation.

CONCLUSION

AB and GB could be novel prebiotic ingredients because they can stimulate the growth and metabolism of probiotics and induce overall beneficial changes in human colonic microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

AB and GB stimulated the growth and metabolism of probiotics, in addition to induce beneficial alterations in human colonic microbiota composition and increase short-chain fatty acid production. These results characterize AB and GB as potential prebiotic ingredients and fruit processing by-products as sources of added-value compounds.

Efficacy of oregano and rosemary essential oils to affect morphology and membrane functions of noncultivable sessile cells of Salmonella Enteritidis 86 in biofilms formed on stainless steel

AIMS

This study evaluated the efficacy of essential oil from Origanum vulgare L. (oregano; OVEO) and Rosmarinus officinalis L. (rosemary; ROEO) to inactivate sessile cells of Salmonella enterica serovar Enteritidis 86 (SE86) in young and mature biofilms formed on stainless steel.

METHODS AND RESULTS

Ultrastructural alterations and damage in different physiological functions caused by OVEO and ROEO in noncultivable sessile cells of SE86 were investigated using scanning electron microscopy and flow cytometry. OVEO (2·5 μl ml^-1 ) and ROEO (40 μl ml^-1 ) were effective to eradicate young and mature biofilms formed by SE86 sessile cells on stainless steel surfaces; however, the efficacy varied with exposure time. OVEO and ROEO caused alterations in morphology of SE86 sessile cells, inducing the occurrence of bubbles or spots on cell surface. OVEO and ROEO compromised membrane polarization, permeability and efflux activity in noncultivable SE86 sessile cells. These findings show that OVEO and ROEO act by a multitarget mechanism on SE86 membrane functions.

CONCLUSIONS

ROEO and OVEO showed efficacy to eradicate SE86 sessile cells in preformed biofilms on stainless steel, displaying a time-dependent effect and multitarget action mode on bacterial cell membrane.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study provides for the first time the effects of OVEO and ROEO on morphology and physiological functions of noncultivable sessile cells of S. Enteritidis biofilms preformed on stainless steel surfaces.

Suppression of Rayleigh-Taylor turbulence by time-periodic acceleration

The dynamics of Rayleigh-Taylor turbulence convection in the presence of an alternating, time-periodic acceleration is studied by means of extensive direct numerical simulations of the Boussinesq equations. Within this framework, we discover a mechanism of relaminarization of turbulence: the alternating acceleration, which initially produces a growing turbulent mixing layer, at longer times suppresses turbulent fluctuation and drives the system toward an asymptotic stationary configuration. Dimensional arguments and linear stability theory are used to predict the width of the mixing layer in the asymptotic state as a function of the period of the acceleration.

Efficacy of trans-nasal fiberendoscopic injection laryngoplasty with centrifuged autologous fat in the treatment of glottic insufficiency due to unilateral vocal fold paralysis

SUMMARY

The objective of this work is to evaluate the safety, feasibility and efficacy of trans-nasal fiberendoscopic injection laryngoplasty (IL) with centrifuged autologous fat, performed under local anaesthesia, in the treatment of glottic insufficiency due to unilateral vocal fold paralysis (UVFP). It is a within-subject study with follow-up 1 week after phonosurgery and after 6 months. A total of 22 patients with chronic dysphonia caused by glottic insufficiency due to UVFP were enrolled. Each patient underwent trans-nasal IL with centrifuged autologous fat through flexible operative endoscope under local anaesthesia and was evaluated before and twice (1 week and 6 months) after phonosurgery, using a multidimensional set of investigations. The assessment protocol included videolaryngostroboscopy, perceptual evaluation of dysphonia, maximum phonation time and patient's self-assessment on voice-related quality of life (QOL) with the Voice Handicap Index-10 and the comparative self-assessment on vocal fatigue and voice quality pre-post treatment. Trans-nasal IL with centrifuged autologous fat was performed in all 22 patients and there were no complications in any case. Significant improvements in videolaryngostroboscopic findings, perceptual evaluation of dysphonia, maximum phonation time and QoL self-assessment were reported after 1 week and were maintained at 6 months. In one patient, the result after 6 months was not satisfactory and this patient then underwent a medialization laryngoplasty (thyroplasty type I) with satisfactory long-term results. In conclusion, trans-nasal fiberendoscopic IL with centrifuged autologous fat seems to be a safe, feasible and efficacious phonosurgical procedure for treatment of glottic insufficiency due to unilateral vocal fold paralysis.

Red Blood Cell Hexokinase in Tumor Bearing Mice

Red blood cell hexokinase of tumor-bearing BALB/c mice was found to be 35% higher than in the normal controls, whereas glucose 6-phosphate-dehydrogenase and other red blood cell glycolytic enzymes were in the normal range. This hexokinase increase cannot be explained by a mean younger red cell population because normal hematological data and normal red cell enzymes, known as red cell age-markers, have been found in tumor-bearing mice. The isozymic pattern of red cell hexokinase is not modified in the tumor-bearing mice.

Relationship between Erythrocyte Hexokinase in Cancer Patients and Red Cell Age

A study of hexokinase isozymic pattern and age dependence of the enzyme was carried out on erythrocytes of 4 patients with adenocarcinoma of the gastrointestinal tract. On the basis of our results, we think that the increase in hexokinase activity previously reported and the increase in both subtypes (Ia and Ib) of the enzyme herein described are not due to a mean younger red cell population caused by secondary anemia, which is frequently present in cancer patients.

Endothelial cells, endoplasmic reticulum stress and oxysterols

Oxysterols are bioactive lipids that act as regulators of lipid metabolism, inflammation, cell viability and are involved in several diseases, including atherosclerosis. Mounting evidence linked the atherosclerosis to endothelium dysfunction; in fact, the endothelium regulates the vascular system with roles in processes such as hemostasis, cell cholesterol, hormone trafficking, signal transduction and inflammation. Several papers shed light the ability of oxysterols to induce apoptosis in different cell lines including endothelial cells. Apoptotic endothelial cell and endothelial denudation may constitute a critical step in the transition to plaque erosion and vessel thrombosis, so preventing the endothelial damaged has garnered considerable attention as a novel means of treating atherosclerosis. Endoplasmic reticulum (ER) is the site where the proteins are synthetized and folded and is necessary for most cellular activity; perturbations of ER homeostasis leads to a condition known as endoplasmic reticulum stress. This condition evokes the unfolded protein response (UPR) an adaptive pathway that aims to restore ER homeostasis. Mounting evidence suggests that chronic activation of UPR leads to cell dysfunction and death and recently has been implicated in pathogenesis of endothelial dysfunction. Autophagy is an essential catabolic mechanism that delivers misfolded proteins and damaged organelles to the lysosome for degradation, maintaining basal levels of autophagic activity it is critical for cell survival. Several evidence suggests that persistent ER stress often results in stimulation of autophagic activities, likely as a compensatory mechanism to relieve ER stress and consequently cell death. In this review, we summarize evidence for the effect of oxysterols on endothelial cells, especially focusing on oxysterols-mediated induction of endoplasmic reticulum stress.

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Endothelial cells dysfunction is critical in the process of atherothrombosis.

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Endoplasmic reticulum stress is a key component in endothelial cell dysfunction.

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Oxysterols are oxidation products of cholesterol found in atherosclerosis lesions.

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Oxysterols are potential modulators of endoplasmic reticulum stress.

Efficacy and Toxicity of Long-Term Administration of 2′,3′-dideoxycytidine in the LP-BM5 Murine-Induced Immunodeficiency Model

The LP-BM5 murine retrovirus-induced immunodeficiency model was used to evaluate the efficacy and toxicity of long-term 2′,3′-dideoxycytidine (DDC) therapy. A mean plasma drug concentration of 0.2 + 0.02 μm of DDC for 3 months was found to reduce splenomegaly, lymphoadenopathy and hypergammaglobulinemia in infected mice. However, DDC also reduced spleen weight in control mice and spleen haemopoiesis in both infected and uninfected animals. In the bone marrow the most prominent feature of DDC treatment was a marked reduction of megakariocytes, while in the liver an hepatocellular vacuolation was evident in uninfected animals. DDC reduced, but did not prevent, LP-BM5 integration in lymph node DNA and Pr 60gag expression in spleen lymphocytes and bone marrow cells. Furthermore, DDC reduced the mitochondrial DNA content and restored the mitogen proliferation of T cells but not that of B cells in infected mice. Thus, DDC appears to be of some, but limited, efficacy in murine AIDS, with a toxicity profile involving more cell types than previously thought.

The Inhibitory Effect of ddC on Human Immunodeficiency Virus Replication Diminishes in Cells that are Chronically Exposed to the Drug

One possible explanation for the failure of human immunodeficiency virus type 1 (HIV-1) antiretroviral inhibitors to block the clinical progression of the infection may be a failure to maintain adequate drug levels at the site of viral replication. We have previously found that exposure of human monoblastoid cells (U937) for several months to a therapeutically relevant concentration (0.1 μM) of 2′,3′-dideoxycytidine (zalcitabine, ddC) allowed the isolation of a drug-resistant cell line characterized by a normal drug transport but a reduced ability to accumulate 2′,3′-dideoxycytidine 5′-triphosphate (the active antiretroviral form of the drug). In this paper we show that the drug-resistant cells were indistinguishable from normal cells in terms of surface CD4 receptors. The susceptibility of parental and ddC-resistant U937 cells to infection by HIV-1 was similar, as measured by proviral DNA formation. However, HIV-1 p24 production and the number of infectious virus particles produced were significantly lower in the drug-resistant compared to control cells. Addition of 0.1 μM ddC inhibited viral production by up to 92% in the control cells but had no effect on ddC-resistant cells. Thus, human cells exposed to therapeutically relevant ddC concentrations for several months show a reduced ddC anabolism and allow ddC-sensitive HIV-1 to replicate in the presence of inhibitory ddC concentrations.

Inhibition of HIV-1 and LP-BM5 Replication in Macrophages by Dideoxycytidine and Dideoxycytidine 5′-Triphosphate

The antiviral agent 2′,3′-dideoxycytidine (ddC) has been shown to be active against HIV-1 infectivity. However, conflicting results have been reported concerning its efficacy in macrophages. Because macrophages possess low levels of the kinase(s) responsible for ddC phosphorylation, we investigated the ability of ddC and 2′,3′-dideoxycytidine 5′-trisphosphate (ddCTP) to suppress HIV-1 and LP-BM5 replication in these cells. Retrovirus replication was only partially inhibited in the two systems investigated by a high (1 μM) ddC concentration. The direct administration of ddCTP, using autologous red blood cells as a delivery system, was found to inhibit HIV-1 and LP-BM5 replication by more than 90% in macrophages without affecting major cell functions. These data, together with those already reported for FIV [Magnani et al. (1994) AIDS Res Hum Retroviruses 10: 1179-1186], suggest that the anabolic phosphorylation of ddC is an important determinant of its anti-HIV activity and that pharmacological interventions that modulate ddC metabolism may be useful for improving its antiretroviral activity in macrophages.

Recent advances in synthesis, characterization of hydroxyapatite/polyurethane composites and study of their biocompatible properties

The development of engineered biomaterials that mimic bone tissues is a promising research area that benefits from a growing interest. Polymers and polymer-ceramic composites are the principle materials investigated for the development of synthetic bone scaffolds thanks to their proven biocompatibility and biostability. Several polymers have been combined with calcium phosphates (mainly hydroxyapatite) to prepare nanocomposites with improved biocompatible and mechanical properties. Here, we report the hydrothermal synthesis in high pressure conditions of nanostructured composites based on hydroxyapatite and polyurethane functionalized with carboxyl and thiol groups. Cell-material interactions were investigated for potential applications of these new types of composites as coating for orthopedic implants. Physical-chemical and morphological characteristics of hydroxyapatite/polyurethane composites were evaluated for different compositions, showing their dependence on synthesis parameters (pressure, temperature). In vitro experiments, performed to verify if these composites are biocompatible cell culture substrates, showed that they are not toxic and do not affect cell viability.

Nanoparticle encapsulation in red blood cells enables blood-pool magnetic particle imaging hours after injection

Magnetic particle imaging (MPI) is a new medical imaging approach that is based on the nonlinear magnetization response of super-paramagnetic iron oxide nanoparticles (SPIOs) injected into the blood stream. To date, real-time MPI of the bolus passage of an approved MRI SPIO contrast agent injected into the tail vein of living mice has been demonstrated. However, nanoparticles are rapidly removed from the blood stream by the mononuclear phagocyte system. Therefore, imaging applications for long-term monitoring require the repeated administration of bolus injections, which complicates quantitative comparisons due to the temporal variations in concentration. Encapsulation of SPIOs into red blood cells (RBCs) has been suggested to increase the blood circulation time of nanoparticles. This work presents first evidence that SPIO-loaded RBCs can be imaged in the blood pool of mice several hours after injection using MPI. This finding is supported by magnetic particle spectroscopy performed to quantify the iron concentration in blood samples extracted from the mice 3 and 24 h after injection of SPIO-loaded RBCs. Based on these results, new MPI applications can be envisioned, such as permanent 3D real-time visualization of the vessel tree during interventional procedures, bleeding monitoring after stroke, or long-term monitoring and treatment control of cardiovascular diseases.

Genomic DNA in human blastocoele fluid

IVF often requires embryo cryopreservation through vitrification. During the vitrification process, the embryos can be collapsed by withdrawing the blastocoele fluid. The metabolomic profile of blastocoele fluid has been recently investigated by high-performance liquid chromatography-electrospray ionization-mass spectrometry to provide metabolite information that can help estimations of implantation efficiency. However, the presence of embryo DNA in blastocoele fluid has not been reported to date. This study shows using real-time PCR that genomic DNA was present in about 90% of blastocoele fluid samples harvested during the vitrification procedure. Moreover, the potential for determining embryo sex directly from blastocoele fluid is demonstrated by amplifying the multicopy genes TSPY1 (on the Y chromosome) and TBC1D3 (on chromosome 17). This opens up the possibility of screening embryos from couples carrying an X-linked disorder to identify male embryos at high risk of disease. The application of whole-genome amplification technologies to fluid samples is also shown to be feasible, potentially allowing more comprehensive genetic tests. As proof of principle, microarray comparative genomic hybridization was attempted to confirm the sex of embryos as well as detect several aneuploidies. However, further studies are needed to validate this approach and confirm that the accuracy is sufficient for diagnostic purposes.

Glucocorticoid resistance in Crohn's disease and ulcerative colitis: an association study investigating GR and FKBP5 gene polymorphisms

The aim of this study is to investigate the role of single-nucleotide polymorphisms (SNPs) of the glucocorticoid receptor (GR) and of the related co-chaperone FKBP5 genes in the development of glucocorticoid (GC) resistance in Crohn's disease (CD) and ulcerative colitis (UC) patients. We have developed a high-resolution DNA melting method that allows simultaneous identification of GR (BclI, N363S and ER22/23EK) and FKBP5 (rs3800373, rs1360780 and rs4713916) polymorphisms. Genotype frequencies were determined in 100 consecutive CD and 100 UC patients under GCs therapy (50 responders and 50 resisters). The variation of FKBP5 polymorphism rs4713916 (G/A), in the putative promoter region of FKBP5, is significantly associated with resistance to GC treatment in CD (responder=17% versus resister=35%; P=0.0043). No significant differences were found in UC patients. If these preliminary findings will be confirmed, the combination of GR and FKBP5 mutational analyses could help to identify subgroups of CD patients with higher chances to benefit from GC treatment.

Electrical characterization of DNA-functionalized solid state nanopores for bio-sensing

We present data concerning the electrical properties of a class of biosensor devices based on bio-functionalized solid state nanopores able to detect different kinds of interactions between probe molecules, chemically attached to the pore surface, and target molecules present in solution and electrophoretically drawn through the nanometric channel. The great potentiality of this approach resides in the fact that the functionalization of a quite large pore (up to 50-60 nm) allows a sufficient diameter reduction for the attainment of a single molecule sensing dimension and selective activation, without the need for further material deposition, such as metal or oxides, or localized surface modification. The results indicate that it will be possible, in the near future, to conceive and design devices for parallel analysis of biological samples made of arrays of nanopores differently functionalized, fabricated by standard lithographic techniques, with important applications in the field of molecular diagnosis.

Improved cellular uptake of functionalized single-walled carbon nanotubes

Single-walled carbon nanotubes (SWNTs) due to their unique structural and physicochemical properties, have been proposed as delivery systems for a variety of diagnostic and therapeutic agents. However, SWNTs have proven difficult to solubilize in aqueous solution, limiting their use in biological applications. In an attempt to improve SWNTs' solubility, biocompatibility, and to increase cell penetration we have thoroughly investigated the construction of carbon scaffolds coated with aliphatic carbon chains and phospholipids to obtain micelle-like structures. At first, oxidized SWNTs (2370 ± 30 nmol mg(-1) of SWNTs) were covalently coupled with an alcoholic chain (stearyl alcohol, C(18)H(37)OH; 816 nmol mg(-1) of SWNTs). Subsequently, SWNTs-COOC(18)H(37) derivatives were coated with phosphatidylethanolamine (PE) or -serine (PS) phospholipids obtaining micelle-like structures. We found that cellular uptake of these constructs by phagocytic cells occurs via an endocytotic mechanism for constructs larger than 400 nm while occurs via diffusion through the cell membrane for constructs up to 400 nm. The material that enters the cell by phagocytosis is actively internalized by macrophages and localizes inside endocytotic vesicles. In contrast the material that enters the cells by diffusion is found in the cell cytosol. In conclusion, we have realized new biomimetic constructs based on alkylated SWNTs coated with phospholipids that are efficiently internalized by different cell types only if their size is lower than 400 nm. These constructs are not toxic to the cells and could now be explored as delivery systems for non-permeant cargoes.

Ultrasound-detected synovitis with power Doppler signal is associated with severe radiographic damage and reduced cartilage thickness in hand osteoarthritis

OBJECTIVES

To examine ultrasound (US) features of synovitis in hand osteoarthritis (OA) joints, and to evaluate their relationship with radiological damage severity and US-detected cartilage thickness.

METHODS

US examination was carried out on 14 joints of both hands of 25 patients with symptomatic hand OA (HOA) and 10 age- and sex-matched control subjects. US-detected features were: synovial hypertrophy, effusion, power Doppler signal (PDS), cartilage thickness. Conventional hand radiographs were scored utilizing the Kellgren-Lawrence and Kallman systems. HOA patients were divided into two subsets: non-erosive and erosive.

RESULTS

Among the three groups of subjects studied, erosive OA showed the highest values of radiological scores and the highest prevalence of US-detected synovitis. Joints positive for US synovitis features (above all PDS) had higher radiological scores and lower cartilage thickness, while joints with X-ray detected central erosions [the hallmark of erosive HOA were more likely to present PDS positivity. US measured cartilage thickness inversely correlated with radiological damage scores.

CONCLUSIONS

US-detected synovitis is present in about 10% of HOA finger joints and is associated with more severe radiological damage and reduced cartilage thickness. PDS and cartilage thickness (mm) may represent two innovative additional information tools provided by ultrasonography in HOA evaluation.

Genetic modulation of the Let-7 microRNA binding to KRAS 3'-untranslated region and survival of metastatic colorectal cancer patients treated with salvage cetuximab-irinotecan

There is increasing evidence that the Let-7 microRNA (miRNA) exerts an effect as a tumor suppressor by targeting the KRAS mRNA. The Let-7 complementary site (LCS6) T>G variant in the KRAS 3'-untranslated region weakens Let-7 binding. We analyzed whether the LCS6 variant may be clinically relevant to patients with metastatic colorectal cancer (MCRC) treated with anti-epidermal growth factor receptor (EGFR) therapy. LCS6 genotypes and KRAS/BRAF mutations were determined in the tumor DNA of 134 patients with MCRC who underwent salvage cetuximab-irinotecan therapy. There were 34 G-allele (T/G+G/G) carriers (25%) and 100 T/T genotype carriers (75%). G-allele carriers were significantly more frequent in the KRAS mutation group than in patients with KRAS wild type (P=0.004). In the 121 patients without BRAF V600E mutation, overall survival (OS) and progression-free survival (PFS) times were compared between carriers of the LCS6 G-allele genotypes and carriers of the wild-type T/T genotype. LCS6 G-allele carriers showed worse OS (P=0.001) and PFS (P=0.004) than T/T genotype carriers (confirmed in the multivariate model including the KRAS status). In the exploratory analysis of the 55 unresponsive patients with KRAS mutation, LCS6 G-allele carriers showed adverse OS and PFS times. These findings deserve additional investigations as they may open novel perspectives for the treatment of patients with MCRC.

A multiplex magnetic capture hybridization and multiplex Real-Time PCR protocol for pathogen detection in seafood

Seafood could become a source of bacterial pathogens by exposure to contaminated water or through processing practices, thus representing a public health hazard. Conventional culture-based analytical methods take several days to be completed, while the molecular rapid identification of bacterial pathogens is crucial for effective disease control. The developed application consist of a multiplex magnetic capture hybridisation (mMCH) assay for the simultaneous isolation of Salmonella spp. and Listeria monocytogenes DNA from seafood, using paramagnetic amino-modified nanoparticles with capture oligonucleotides, and a triplex Real-Time PCR with an Internal Amplification Control (IAC), in accordance with ISO 22174. The detection probability was 100% with 10 genome equivalents of each target species co-amplified in the same reaction. The complete molecular procedure was tested on raw and smoked salmon fillets artificially contaminated with known amounts of one or both target bacteria (1-10(3)cfu/g), directly or after culture enrichment, and compared for equivalence with the standard methods. Results revealed a complete agreement between the two approaches, with a sensitivity of 1 cfu/g, in enriched samples, and higher sensitivity (10(2)-10(3)cfu/g) of the molecular method in samples examined before culture enrichment. The proposed procedure was also able to identify a natural contamination by L. monocytogenes in smoked salmon with a considerable shortening of time.

Parallel conduction of the phase I preventive and therapeutic trials based on the Tat vaccine candidate

The native HIV-1 Tat protein was chosen as vaccine candidate for phase I clinical trials in both uninfected (ClinicalTrials.gov identifier: NCT00529698) and infected volunteers (ClinicalTrials.gov identifier: NCT00505401). The rationale was based on the role of Tat in the natural infection and AIDS pathogenesis, on the association of Tat-specific immune responses with the asymptomatic stage and slow-progression rate as well as on its sequence conservation among HIV clades (http://www.hiv1tat-vaccines.info/). The parallel conduction in the same clinical centers of randomized, double blind, placebo-controlled phase I studies both in healthy, immunologically competent adults and in HIV-infected, clinically asymptomatic, individuals represents a unique occasion to compare the vaccine-induced immune response in both the preventive and therapeutic setting. In both studies, the same lot of the native Tat protein was administered 5 times, every four weeks, subcute (SC) with alum adjuvant or intradermic (ID), in the absence of adjuvant, at 7.5 microg, 15 microg or 30 microg doses, respectively. The primary and secondary endpoints of these studies were the safety and immunogenicity of the vaccine candidate, respectively. The study lasted 52 weeks and monitoring was conducted for on additional 3 years. The results of both studies indicated that the Tat vaccine is safe and well tolerated both locally and systemically and it is highly immunogenic at all the dosages and by both routes of administration. Vaccination with Tat induced a balanced immune response in uninfected and infected individuals. In particular, therapeutic immunization induced functional antibodies and partially reverted the marked Th1 polarization of anti-Tat immunity seen in natural infection, and elicited a more balanced Th1/Th2 immune response. Further, the number of CD4 T cells correlated positively with anti-Tat antibody titers. Based on these results, a phase II study is ongoing in infected drug-treated individuals (http://www.hiv1tat-vaccines.info/).

Expression and characterization of the periplasmic cobalamin-binding protein of Photobacterium damselae subsp. piscicida

Abstract Cobalamin (vitamin B(12)) is an essential cofactor in a variety of enzymatic reactions and most prokaryotes contain transport systems to import vitamin B(12). A gene coding for a periplasmic cobalamin-binding protein of Photobacterium damselae subsp. piscicida was identified by in silico analysis of sequences from a genomic library. The open reading frame was composed of 834 bp encoding a protein of 277 amino acids. The protein showed 61% identity with the vitamin B(12)-binding protein precursor of P. profundum, 53% identity with the corresponding protein of Vibrio parahaemolyticus and 43% identity with the periplasmic binding protein BtuF of Escherichia coli. The expression of the native protein was investigated in P. damselae subsp. piscicida, but BtuF was weakly expressed under normal conditions. To characterize the BtuF of P. damselae subsp. piscicida, the recombinant protein was expressed with a C-terminal His(6)-tag and purified; the molecular weight was estimated to be approximately 30 kDa. The protein does not contain any free thiol group, consistent with the view that the two cysteine residues are involved in a disulphide bond. The purified BtuF binds cyanocobalamin with an affinity constant of 6 +/- 2 microm.

Development of a multiplex PCR assay for Photobacterium damselae subsp. piscicida identification in fish samples

A multiplex polymerase chain reaction protocol for the detection of Photobacterium damselae and subspecies piscicida and damselae discrimination, with internal amplification control, was developed. Assay specificity was assessed by testing 19 target and 25 non-target pure cultures. The detection limit was 500 fg, corresponding to 100 genome equivalents. The optimized protocol was also prevalidated with spleen, kidney and blood samples from infected and uninfected sea bass, without any culture step, and it can be proposed as a valid alternative to culture standard methods for the rapid and specific diagnosis of photobacteriosis in fish.

KRAS codon 61, 146 and BRAF mutations predict resistance to cetuximab plus irinotecan in KRAS codon 12 and 13 wild-type metastatic colorectal cancer

Background:

KRAS codons 12 and 13 mutations predict resistance to anti-EGFR monoclonal antibodies (moAbs) in metastatic colorectal cancer. Also, BRAF V600E mutation has been associated with resistance. Additional KRAS mutations are described in CRC.

Methods:

We investigated the role of KRAS codons 61 and 146 and BRAF V600E mutations in predicting resistance to cetuximab plus irinotecan in a cohort of KRAS codons 12 and 13 wild-type patients.

Results:

Among 87 KRAS codons 12 and 13 wild-type patients, KRAS codons 61 and 146 were mutated in 7 and 1 case, respectively. None of mutated patients responded vs 22 of 68 wild type (P=0.096). Eleven patients were not evaluable. KRAS mutations were associated with shorter progression-free survival (PFS, HR: 0.46, P=0.028). None of 13 BRAF-mutated patients responded vs 24 of 74 BRAF wild type (P=0.016). BRAF mutation was associated with a trend towards shorter PFS (HR: 0.59, P=0.073). In the subgroup of BRAF wild-type patients, KRAS codons 61/146 mutations determined a lower response rate (0 vs 37%, P=0.047) and worse PFS (HR: 0.45, P=0.023). Patients bearing KRAS or BRAF mutations had poorer response rate (0 vs 37%, P=0.0005) and PFS (HR: 0.51, P=0.006) compared with KRAS and BRAF wild-type patients.

Conclusion:

Assessing KRAS codons 61/146 and BRAF V600E mutations might help optimising the selection of the candidate patients to receive anti-EGFR moAbs.

Different prelamin A forms accumulate in human fibroblasts: a study in experimental models and progeria

Lamin A is a component of the nuclear lamina mutated in a group of human inherited disorders known as laminopathies. Among laminopathies, progeroid syndromes and lipodystrophies feature accumulation of prelamin A, the precursor protein which, in normal cells, undergoes a multi-step processing to yield mature lamin A. It is of utmost importance to characterize the prelamin A form accumulated in each laminopathy, since existing evidence shows that drugs acting on protein processing can improve some pathological aspects.We report that two antibodies raised against differently modified prelamin A peptides show a clear specificity to full-length prelamin A or carboxymethylated farnesylated prelamin A, respectively. Using these antibodies, we demonstrated that inhibition of the prelamin A endoprotease ZMPSTE24 mostly elicits accumulation of full-length prelamin A in its farnesylated form, while loss of the prelamin A cleavage site causes accumulation of carboxymethylated prelamin A in progeria cells. These results suggest a major role of ZMPSTE24 in the first prelamin A cleavage step.

Association of BRAF mutations and EGFR Intron-1 L/L genotype with resistance to cetuximab plus irinotecan treatment in KRAS wild-type metastatic colorectal cancer patients

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Background: KRAS and BRAF mutations are associated with resistance to anti-EGFR monoclonal antibodies. EGFR Intron-1 (CA)n genotype has been suggested to influence the activity of cetuximab. Methods: We retrospectively assessed KRAS and BRAF mutational status and EGFR Intron-1 (CA)n genotypes in 117 irinotecan-refractory EGFR-positive mCRC patients treated with cetuximab plus irinotecan. We defined short (S) and long (L) allelic variants those presenting < and ≥17 CA repeats respectively. Among KRAS wild-type patients, we investigated the association between BRAF mutational status and EGFR Intron-1 genotype and treatment outcome in terms of RR and PFS. Results: Among 66 (56%) KRAS wild-type patients, BRAF V600E mutation was detected in 9 (14%) patients. BRAF wild-type patients reported improved RR (0/9, 0% vs 19/57, 33%, p = 0.04) and PFS (3.3 vs 5.1 months, p = 0.076; HR = 0.54 [95%CI: 0.18–1.09]) in comparison with BRAF-mutated. EGFR Intron-1 L/L genotype was detected in 13 (20%) KRAS wild-type patients. Objective responses were reported in 1/13 (8%) EGFR Intron-1 L/L patients and in 18/53 (34%) S/L or S/S patients (p = 0.061). Significantly longer PFS was observed among EGFR Intron-1 S/L or S/S patients (5.3 vs 3.3 months, p = 0.0062; HR = 0.45 [95%CI: 0.14–0.72]). Among 57 KRAS and BRAF wild-type patients, 1/11 (9%) EGFR Intron-1 L/L patients and 18/46 (39%) S/L - S/S patients responded to treatment (p = 0.058), achieving median PFS of 3.7 and 5.4 months, respectively (p = 0.022; HR = 0.48 [95%CI: 0.15–0.87]). Conclusions: In KRAS wild-type patients, BRAF mutations are confirmed to predict resistance to cetuximab treatment. EGFR Intron-1 allelic variants are promising markers of benefit in patients with both KRAS and BRAF wild-type and may help to better select mCRC patients candidate to receive cetuximab-containing treatment.

No significant financial relationships to disclose.

Different prelamin A forms accumulate in human fibroblasts: a study in experimental models and progeria

Lamin A is a component of the nuclear lamina mutated in a group of human inherited disorders known as laminopathies. Among laminopathies, progeroid syndromes and lipodystrophies feature accumulation of prelamin A, the precursor protein which, in normal cells, undergoes a multi-step processing to yield mature lamin A. It is of utmost importance to characterize the prelamin A form accumulated in each laminopathy, since existing evidence shows that drugs acting on protein processing can improve some pathological aspects. We report that two antibodies raised against differently modified prelamin A peptides show a clear specificity to full-length prelamin A or carboxymethylated farnesylated prelamin A, respectively. Using these antibodies, we demonstrated that inhibition of the prelamin A endoprotease ZMPSTE24 mostly elicits accumulation of full-length prelamin A in its farnesylated form, while loss of the prelamin A cleavage site causes accumulation of carboxymethylated prelamin A in progeria cells. These results suggest a major role of ZMPSTE24 in the first prelamin A cleavage step.