Filamentation of a relativistic proton bunch in plasma.

We show in experiments that a long, underdense, relativistic proton bunch propagating in plasma undergoes the oblique instability, which we observe as filamentation. We determine a threshold value for the ratio between the bunch transverse size and plasma skin depth for the instability to occur. At the threshold, the outcome of the experiment alternates between filamentation and self-modulation instability (evidenced by longitudinal modulation into microbunches). Time-resolved images of the bunch density distribution reveal that filamentation grows to an observable level late along the bunch, confirming the spatiotemporal nature of the instability. We provide a rough estimate of the amplitude of the magnetic field generated in the plasma by the instability and show that the associated magnetic energy increases with plasma density.

Hosing of a Long Relativistic Particle Bunch in Plasma.

Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing.

Quantitative and qualitative features of acute phase-adverse events following SARS-CoV-2 vaccination in a large sample of people with multiple sclerosis.

INTRODUCTION: Few data are available on adverse events (AE) associated to vaccines in persons with multiple sclerosis (pwMS). AIMS: to study the incidence of acute phase AE (AP-AE) related to SARS-CoV-2 mRNA vaccines in pwMS compared to a control group, and to analyze the association between AP-AE and disease modifying treatments (DMT). METHODS: This was a cross-sectional study on 438 PwMS and 481 age- and sex-matched subjects not affected by dysimmune diseases that underwent two doses of SARS-CoV-2 mRNA BNT162b2 vaccine (Pfizer/BioNtech). RESULTS: Two hundred and twenty five (51.4%) pwMS complained of ≥1 AP-AE after the first dose, 269 (61.4%) after the second dose. A logistic regression analysis revealed that only pwMS on Fingolimod and Ocrelizumab did not show a higher risk of developing AP-AE. The likelihood to present with ≥1 AP-AE, after correcting for age and sex, was significantly higher in pwMS than controls. CONCLUSIONS: This study reports qualitative and quantitative features of AP-AE associated with the first and second doses of SARS-CoV-2 vaccine in a large sample of pwMS. The only risk factor identified for developing AP-AE is female gender. AntiCD-20 monoclonal antibodies and S1P inhibitors are associated with a lower risk of AP-AE occurrence.

Controlled Growth of the Self-Modulation of a Relativistic Proton Bunch in Plasma.

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.

Lipid nano-vesicles for thyroid hormone encapsulation: A comparison between different fabrication technologies, drug loading, and an in vitro delivery to human tendon stem/progenitor cells in 2D and 3D culture.

Phosphatidylcholine (PC) vesicles loaded with Triiodothyronine (T3) were fabricated using different manufacturing methods: thin layer hydration plus sonication (TF-UF), supercritical liposome formation (SC), and microfluidic technology (MF). Vesicles obtained by MF had the lowest mean diameter (88.61 ± 44.48 nm) with a Zeta Potential of -20.1 ± 5.90 mV and loading of 10 mg/g (encapsulation efficiency: 57%). In contrast, SC vesicles showed extremely low encapsulation efficiency (<10%) probably due to T3 solubility in ethanol/carbon dioxide mixture; despite TF-UF vesicles exhibiting good size (167.7 ± 90 nm; Zp -8.50 ± 0.60 mV) and loading (10 mg/g), poor mass recovery was obtained (50% loss). MF vesicles had low cytotoxicity, and they were well enough internalized by both HeLa and human tendon stem/progenitor cells (hTSPCs). Their biological activity was also monitored in both 2D and 3D cultures of hTSPCs supplemented with therapeutical concentrations of PC/T3 nano-liposomes. 2D culture showed almost similar constitutive gene expression compared to control culture supplemented with free-T3. On the contrary, when hTPSCs 3D culture was assembled, it showed a more evident homogeneous distribution of FITC labeled vesicles within the high-density structure and a significant upregulation of cell constitutive genes, such as type I Collagen (4.8-fold; p < 0.0001) at day 7, compared to the control, suggesting that T3/PC formulation has increased T3 cytosolic concentration, thus improving cells metabolic activity. The study supported MF technology for nano-carriers fabrication and opens perspectives on the activity of PC/T3 nano-vesicles as innovative formulations for TPSCs stimulation in ECM secretion.

Myogenic commitment of human stem cells by myoblasts Co-culture: a static vs. a dynamic approach.

An in-vitro model of human bone marrow mesenchymal stem cells (hBM-MSCs) myogenic commitment by synergic effect of a differentiation media coupled with human primary skeletal myoblasts (hSkMs) co-culture was developed adopting both conventional static co-seeding and perfused culture systems. Static co-seeding provided a notable outcome in terms of gene expression with a significant increase of Desmin (141-fold) and Myosin heavy chain II (MYH2, 32-fold) at day 21, clearly detected also by semi-quantitative immunofluorescence. Under perfusion conditions, myogenic induction ability of hSkMs on hBM-MSCs was exerted by paracrine effect with an excellent gene overexpression and immunofluorescence detection of MYH2 protein; furthermore, due to the dynamic cell culture in separate wells, western blot data were acquired confirming a successful cell commitment at day 14. A significant increase of anti-inflammatory cytokine gene expression, including IL-10 and IL-4 (15-fold and 11-fold, respectively) at day 14, with respect to the pro-inflammatory cytokines IL-12A (7-fold at day 21) and IL-1ß (1.4-fold at day 7) was also detected during dynamic culture, confirming the immunomodulatory activity of hBM-MSCs along with commitment events. The present study opens interesting perspectives on the use of dynamic culture based on perfusion as a versatile tool to study myogenic events and paracrine cross-talk compared to the simple co-seeding static culture.

A bioavailability study on microbeads and nanoliposomes fabricated by dense carbon dioxide technologies using human-primary monocytes and flow cytometry assay.

Supercritical Emulsion Extraction (SEE) and Supercritical assisted Liposome formation (SuperLip), use dense gases such as carbon dioxide (dCO2) to fabricate advanced micro/nanocarriers. SEE uses dCO2 to extract solvent from the oily phase of an emulsion and obtain biopolymer microbead; For this study, poly-Lactic Acid (PLA) microbeads of 1 ±â€¯0.2 µm in mean size loaded at 1 µg/mgPLA with Rhodamine B (ROD) were prepared by SEE; the beads showed a solvent residue lower than 10 ppm and encapsulated the fluorochrome with an efficiency of 90%. SuperLip uses dCO2 to enhance lipid/ethanol/water mixing and to promote the ethanol extraction from liposome suspension. In this case, phosphatidyl-choline (PC) vesicles with a mean size of 0.2 ±â€¯0.05 µm and loaded with Fluorescein Iso-ThioCyanate (FITC) at 8 µg/mgPC were prepared; small unilamellar structure was observed for all the vesicles with FITC encapsulation efficiency of 80%. Ethanol residue of 50 ppm was measured in all the liposome suspensions. The bioavailability of microbeads and nanoliposomes was assessed through incubation with human monocytes previously isolated from healthy donors' blood. A specifically optimized protocol that allowed their quenching on the cell surface was developed to monitor by flow cytometer assay only the cell population that effectively internalized the carriers. When microbeads were tested, the percentage of alive internalizing monocytes was of about 30%. An internalization of 96.1 ±â€¯21% was, instead, obtained at dosage of 0.1 mg/mL for nanoliposomes. In this last case, monocytes showed a vitality of almost 100% after vesicles internalization at all the concentrations studied; on the other hand, cell apoptosis progressively increased in a dose/response manner, after polymer microbeads phagocytosis. The proposed data suggested that dCO2 technologies can be reliably used to fabricate intracellular carriers.

Optimum design of family structure and allocation of resources in association mapping with lines from multiple crosses.

Family mapping is based on multiple segregating families and is becoming increasingly popular because of its advantages over population mapping. Athough much progress has been made recently, the optimum design and allocation of resources for family mapping remains unclear. Here, we addressed these issues using a simulation study, resample model averaging and cross-validation approaches. Our results show that in family mapping, the predictive power and the accuracy of quatitative trait loci (QTL) detection depend greatly on the population size and phenotyping intensity. With small population sizes or few test environments, QTL results become unreliable and are hampered by a large bias in the estimation of the proportion of genotypic variance explained by the detected QTL. In addition, we observed that even though good results can be achieved with low marker densities, no plateau is reached with our full marker complement. This suggests that higher quality results could be achieved with greater marker densities or sequence data, which will be available in the near future for many species.

Albumin/gentamicin microspheres produced by supercritical assisted atomization: optimization of size, drug loading and release.

In this work, the supercritical assisted atomization (SAA) is proposed, for the first time, not only as a micronization technology but also as a thermal coagulation process for the production of bovine serum albumin (BSA) microspheres charged with Gentamicin sulfate (GS). Particularly, different water solutions of BSA/GS were processed by SAA to produce protein microspheres with different size and antibiotic content. SAA precipitation temperature was selected in the range 100-130 °C to generate protein coagulation and to recover micronized BSA in form of hydrophobic aggregates; GS loading was varied between 10% and 50% (w/w) with an encapsulation efficiency which often reached 100%. In all cases, spherical and noncoalescing particles were successfully produced with a mean particle size of 2 µm and with a standard deviation of about ±1 µm. The microspheres also showed a good stability and constant water content after 60 days of storage. The release profiles of the entrapped drug were monitored using Franz cells to evaluate the possible application of the produced microspheres in wound dressing formulations. Particularly, the microspheres with a BSA/GS ratio of 4:1 after the first burst effect (of 40% of GS loaded) were able to release the GS continuously over 10 days.

NSAID drugs release from injectable microspheres produced by supercritical fluid emulsion extraction.

Supercritical fluid emulsion extraction is an innovative technology that uses supercritical carbon dioxide (SC-CO(2)) to extract the dispersed oily phase of an emulsion. This technology was used to produce poly-lactic-co-glycolic acid (PLGA) microspheres charged with two common NSAIDs: piroxicam (PX) and diclophenac sodium (DF). Single (O/W) and double (W/O/W) emulsions were tested and a comparative study between the characteristics of the microspheres obtained by SC-CO(2) extraction and the ones produced by conventional solvent evaporation (SE) is proposed. Varying the droplet dimensions, microspheres with mean diameters (MDs) of 1, 2, and 3 microm were obtained; however, the microspheres produced by SC-CO(2) gave always a better reproduction of the MD of original droplets because aggregation phenomena often modify the mean size and distribution of the microparticles produced by SE. Moreover, very efficient drug loadings (88% w/w of DF in PLGA using W/O/W emulsion and 97% of PX w/w in PLGA starting from O/W emulsion) were measured in the products obtained by SC-CO(2), respectively; whereas, the SE produced a drug loading of 30% in the case of double emulsion and of 70% for single emulsion. Solvent residue of 10 ppm was also measured by SC-CO(2) technology against the 600 ppm of the SE products. The release profiles of the entrapped drugs were also monitored to check the structure of the microspheres produced by this new technology.

Corticosteroid microparticles produced by supercritical-assisted atomization: process optimization, product characterization, and "in vitro" performance.

In this work, the production of dexametasone and dexametasone acetate microparticles is proposed using supercritical-assisted atomization (SAA). This process is based on the solubilization of supercritical carbon dioxide in a liquid solution containing the drug; then, the ternary mixture is sprayed through a nozzle and submicroparticles are formed as a consequence of the enhanced atomization. Several process parameters such as different organic solvent (methanol and acetone), solute concentration and flow rate ratio between the liquid solution and carbon dioxide are investigated; their influence is evaluated on the morphology and size of precipitated particles. Spherical corticosteroid particles with mean diameters ranging from 0.5 to 1.2 microm are produced at the optimum operating conditions and narrow particle size distributions (PSDs) have also been obtained. No drug degradation was observed after SAA processing and solvent residues of 300 and 500 ppm for acetone and methanol, respectively, were measured. Drug microparticles produced by SAA can be semi-crystalline or amorphous depending on the process condition; a micronized drug surface area ranging from about 4 to 5 m2/g was also observed. The "in vitro" activity of both untreated and SAA processed glucocorticoids was tested on the release of pro-inflammatory cytokines from stimulated cells. The results shown that SAA-glucocorticoids have retained the activity of the parent untreated compounds and, in the case of dexamethasone, SAA processing improves drug performance.

[Training needs and role of general practitioners for preventing measures and medical surveillance of ex-exposed to occupational carcinogens]. / Bisogni formativi e ruolo dei medici di medicina generale per la prevenzione e la sorveglianza sanitaria degli ex esposti a cancerogeni professionali.

The study was aimed at investigating in a sample of general medicine practitioners the level of epidemiologic and law knowledge as well as the degree of sensitivity to the topic of subjects formerly affected by occupational cancer. From the research, carried out on a sample of 745 practitioners from two northern Italy highly industrialized regions, come out the need for training and information on the problems associated with identification and management of subjects formerly exposed to professional cancer.

Griseofulvin micronization and dissolution rate improvement by supercritical assisted atomization.

Supercritical assisted atomization (SAA) was used to micronize griseofulvin (GF), selected as a model compound, to verify the performance of this innovative process. SAA is based on the solubilization of supercritical carbon dioxide in a liquid solution containing the drug. The ternary mixture is then sprayed through a nozzle and microparticles are formed as a consequence of the enhanced atomization. Precipitation temperature and drug concentration in the liquid solution were studied to evaluate their influence on morphology and size of precipitated particles. A good particle size control was obtained and GF spherical particles with mean diameters ranging from 0.5 to 2.5 microm were produced with a narrow particle size distribution. Processed GF was characterized by high-performance liquid chromatography-UV/vis, headspace-gas chromatography-flame ionization detection, differential scanning calorimetry, BET and X-ray analyses. No drug degradation was observed and a solvent residue (acetone) less than 800 ppm was measured. GF microparticles showed good stability and surface areas ranging from about 4 to 6 m(2) g(-1); moreover, the micronized drug retained the crystalline habit. GF capsules were formulated with starch and used to compare the dissolution rate of SAA-processed and conventional jet-milled drug. A faster dissolution and a better reproducibility of the dissolution profile were observed for SAA-processed GF.

Terbutaline microparticles suitable for aerosol delivery produced by supercritical assisted atomization.

A new micronization technique called supercritical assisted atomization has been used to produce terbutaline microparticles with controlled particle size distribution in the range of drug particles deliverable by aerosol. The process is based on the solubilization of a fixed amount of supercritical carbon dioxide in a liquid solution; then, the ternary mixture is sprayed through a nozzle and atomized in order to produce microparticles. Water has been used as the liquid solvent; heated nitrogen has also been delivered into the precipitator to evaporate the liquid droplets. The process has been first optimized with respect to pressure and temperature (mixing temperature and pressure, precipitation temperature) and very mild operation conditions have been selected; then, the influence of the solute concentration in the liquid solution on particle size has been studied. The terbutaline produced powders were characterized with respect to morphologies and particle size. Spherical particles with very narrow volumetric particle size distributions were produced. Particularly, operating at 30 and 50mg of terbutaline per ml of water, more than 90% of the two distributions ranged between 1 and 3 microm; at 80 mg/ml more than 99% of the distribution ranged between 1 and 4 microm. HPLC analysis confirmed that no chemical degradation occurred in the drug as a consequence of the supercritical processing.

Ampicillin micronization by supercritical assisted atomization.

The micronization technique called supercritical assisted atomization (SAA) was used to produce ampicillin microparticles with controlled particle size and particle size distribution suitable for aerosol drug delivery. The process is based on the solubilization of supercritical CO2 in a liquid solution. The ternary mixture is then sprayed through a nozzle and, as a consequence of enhanced atomization, solid microparticles are formed. Water and organic solvents were tested with ampicillin to determine the influence of the solvent on the process mechanism. SAA process parameters were studied by testing different supercritical/liquid solvent flow ratios, ampicillin concentrations in the liquid solution and nozzle diameters. The effect of these parameters on morphology, particle size and particle size distribution of microparticles was analysed. Ampicillin particles suitable for aerosol delivery in the size range 1-5 microm were obtained using buffered water. Moreover, by varying the solute concentration, ampicillin particles in a narrower range (1-3 microm) than that usually suggested for aerosol deliverable drugs were obtained. This is an example of particle size tailoring by SAA.

Frequent activation of ret protooncogene by fusion with a new activating gene in papillary thyroid carcinomas.

Tumor specific rearrangements of ret gene are frequently detected in papillary thyroid carcinomas. These rearrangements result in the formation of chimeric genes showing the tyrosine kinase domain of ret fused with the 5' end sequences of different genes. We examined a series of 52 patients and identified 10 cases of ret fusion with D10S170 locus resulting in the generation of ret/PTC1 oncogene, 2 cases with the gene encoding the regulatory subunit RI alpha of PKA (ret/PTC2), and finally 6 cases, here described, with a newly discovered gene called ele1 localized on chromosome 10 and leading to the formation of ret/PTC3 oncogene. Our results show the expression of the ret/PTC3 hybrid gene in all the 6 cases and demonstrated its association with the synthesis of 2 constitutively phosphorylated isoforms of the oncoprotein (p75 and p80). The chromosome 10 localization of both ret and ele1 and the detection, in all cases, of a sequence reciprocal to that generating the oncogenic rearrangements, strongly suggest that ret/PTC3 formation is a consequence of an intrachromosomal inversion of chromosome 10.

A t(10;17) translocation creates the RET/PTC2 chimeric transforming sequence in papillary thyroid carcinoma.

Activation of the RET protooncogene tyrosine kinase (tk) by fusion with other genes is a frequent finding in papillary thyroid carcinoma. The tk domain of proto-RET can be fused either with the D10S170 gene generating the RET/PTC1 transforming sequence or with sequences belonging to the gene encoding the regulatory subunit RIA of c-AMP-dependent protein kinase A, thus forming the RET/PTC2 oncogene. We have previously shown that an inversion of chromosome 10, inv(10)(q11.2q21), is responsible for the generation of the RET/PTC1. Here we report that a chromosomal translocation, t(10;17)(q11.2;q23), juxta-poses the tk domain of the RET protooncogene, which resides on chromosome 10, to a 5' portion of the RIA gene on chromosome 17, leading to the formation of the chimeric transforming gene RET/PTC2. The finding of the transforming protein in primary tumor cell extracts supports the conclusion that RET/PTC2 activation plays a role in papillary thyroid tumorigenesis.

Inhibition of hepatitis B virus surface antigen gene expression in carcinogen-induced liver tumors from transgenic mice.

We previously showed that hepatitis B surface antigen (HBsAg)-producing transgenic mice were more sensitive to hepatocarcinogens than their normal littermates were. We have now investigated the regulation of hepatitis B virus (HBV) gene expression in carcinogen-induced liver tumors of HBV-carrier transgenic mice and in three cell lines derived from tumor samples. Transcription of the S gene was repressed in 17 tumors even though they had normal levels of liver-specific mRNAs such as albumin and transferrin. Three hepatoma cell lines, derived from independent tumor samples, were analyzed for their capacity to express the S gene after transfection of cloned DNA. Although they no longer expressed the endogenous S gene, they were still able to express it from transfected viral DNA both transiently and stably. The loss of HBsAg expression in tumors and in the cell lines was accompanied by de novo methylation of the S region, which is a way to permanently repress gene expression. Our data confirm in an animal model previous observations of S-gene expression in human hepatocarcinoma and suggest a role for its downregulation in tumor progression.

Selective activation of ras oncogenes in follicular and undifferentiated thyroid carcinomas.

A total of 96 tumour samples (88 primary tumours and 8 nodal metastases) from 88 patients with thyroid adenomas and carcinomas were investigated for ras gene mutations using polymerase chain reaction, oligonucleotide probing and sequencing. Neither the 19 adenomas nor the 31 papillary carcinomas analysed harboured point mutations. In our cases, mutations in all three ras oncogenes were found in follicular carcinomas (five out of 21) and in the less differentiated thyroid tumour: poorly differentiated carcinomas (three out of 11) and undifferentiated carcinomas (one out of five). Finally, mutated ras oncogenes had a significant association with the appearance of haematogenous (particularly bone) metastases, suggesting a role of ras genes activation in the metastatic capability of these tumours.