Cultivation modes affect the morphology, biochemical composition, and antioxidant and anti-inflammatory properties of the green microalga Neochloris oleoabundans.

Microalgae are considered promising sustainable sources of natural bioactive compounds to be used in biotechnological sectors. In recent years, attention is increasingly given to the search of microalgae-derived compounds with antioxidant and anti-inflammatory properties for nutraceutical or pharmacological issues. In this context, attention is usually focused on the composition and bioactivity of algae or their extracts, while less interest is driven to their biological features, for example, those related to morphology and cultivation conditions. In addition, specific studies on the antioxidant and anti-inflammatory properties of microalgae mainly concern Chlorella or Spirulina. The present work was focused on the characterization of the Chlorophyta Neochloris oleoabundans under two combinations of cultivation modes: autotrophy and glucose-induced mixotrophy, each followed by starvation. Biomass for morphological and biochemical characterization, as well as for extract preparation, was harvested at the end of each cultivation phase. Analyses indicated a different content of the most important classes of bioactive compounds with antioxidant/anti-inflammatory properties (lipids, exo-polysaccharides, pigments, total phenolics, and proteins). In particular, the most promising condition able to prompt the production of antioxidant algal biomass with anti-inflammatory properties was the mixotrophic one. Under mixotrophy, beside an elevated algal biomass production, a strong photosynthetic metabolism with high appression of thylakoid membranes and characteristics of high photo-protection from oxidative damage was observed and linked to the overproduction of exo-polysaccharides and lipids rather than pigments. Overall, mixotrophy appears a good choice to produce natural bioactive extracts, potentially well tolerated by human metabolism and environmentally sustainable.

Last technological advancement in additive manufacturing for cardiovascular applications.

Additive manufacturing (AM) has increasing applications in medicine in recent times. This technology has emerged in cardiovascular medicine as an intelligent system for the improvement of medical devices, the preparation of patient-specific models, and the prototyping of grafts. This review traces the research and development in the production of surgical guides and synthetic grafts for cardiac and vascular applications over the last few years. It also traces the recent widespread use of 3D-printed specific-patient models for cardiovascular surgical interventions. A current view of AM strategies, materials and solutions to improve cardiovascular patient outcomes is also provided.

Antibiotic consumption is a major driver of antibiotic resistance in calves raised on Italian cow-calf beef farms.

Although its importance, little information is available on antibiotic-resistance in cow-calf beef farms. This study aimed to determine prevalence and risk factors for antibiotic-resistant organisms in this livestock system. Fifty-four farms from Central Italy were included to assess the presence of antibiotic-resistant indicator Escherichia coli and of ESBL and/or AmpC-producing E. coli (ESBL/AmpC-EC) in calves. Antimicrobial usage (AMU) was recorded, and farm-related variables were collected through questionnaires. Potential risk factors were tested using a mixed-effects logistic regression model. The presence of resistant-E. coli was recorded in 75.9% of farms (95% confidence interval [CI]: 62.4-86.5) with resistance to tetracyclines, sulfonamides, penicillins, and fluoroquinolones as the most frequent. The prevalence of farms positive for ESBL/AmpC-EC was 35.2% (95% CI: 22.7-49.4). AMU on the farms originating a resistant-E. coli was higher than that on the farms originating a susceptible-E. coli. The same difference was found for the consumption of beta-lactams (beta-DCD/year) and AMU via the parenteral route, which resulted also associated with the presence of ESBL/AmpC-EC. Farms with higher beta-DCD/year had an increased risk of being positive for resistant-E. coli, whereas farms with higher overall AMU had an increased risk for ESBL/AmpC-EC presence. Among farm-related factors, only farm size was associated with the presence of ESBL/AmpC-EC (odds ratio: 5.8, 95% CI: 1.3-26.3). Our findings highlight a reduction of the risk of ESBL/AmpC-EC in small cow-calf farms, and a strong association between AMU and antibiotic-resistance. Antibiotic stewardship programs are needed to improve the health status of cow-calf farms and ensure their long-term sustainability.

Degreening of the unicellular alga Euglena gracilis: thylakoid composition, room temperature fluorescence spectra and chloroplast morphology.

Thylakoid dismantling is one of the most relevant processes occurring when chloroplasts are converted to non-photosynthetically active plastids. The process is well characterised in senescing leaves, but other systems could present different features. In this study, thylakoid dismantling has been analysed in dividing cells of the unicellular alga, Euglena gracilis, cultured in darkness. Changes in photosynthetic pigments and in the abundance of LHC and PSII core proteins (D2 and CP43) showed that: (i) during the 0-24 h interval, the decline in LHCII was faster than that in the PSII core; (ii) during the 24-48 h interval, PSII and LHCII were strongly degraded to nearly the same extent; (iii) in the 48-72 h interval, the PSII core proteins declined markedly, while LHCII was maintained. These changes were accompanied by variations in room temperature fluorescence emission spectra recorded from single living cells with a microspectrofluorimeter (excitation, 436 nm; range 620-780 nm). Emission in the 700-715 nm range was proposed to derive from LHCI-II assemblages; changes in emission at 678 nm relative to PSII matched PSII core degradation phases. Overall, the results suggest that, in degreening E. gracilis, thylakoid dismantling is somewhat different from that associated with senescence, because of the early loss of LHCII. Moreover, it is proposed that, in this alga, disruption of the correct LHCI-II stoichiometry alters the energy transfer to photosystems and destabilises membrane appression leading to the thylakoid destacking observed using transmission electron microscopy.

Powder-based 3D printing for bone tissue engineering.

Bone tissue engineered 3-D constructs customized to patient-specific needs are emerging as attractive biomimetic scaffolds to enhance bone cell and tissue growth and differentiation. The article outlines the features of the most common additive manufacturing technologies (3D printing, stereolithography, fused deposition modeling, and selective laser sintering) used to fabricate bone tissue engineering scaffolds. It concentrates, in particular, on the current state of knowledge concerning powder-based 3D printing, including a description of the properties of powders and binder solutions, the critical phases of scaffold manufacturing, and its applications in bone tissue engineering. Clinical aspects and future applications are also discussed.

Cyto-histological and morpho-physiological responses of common duckweed (Lemna minor L.) to chromium.

Along with cadmium, lead, mercury and other heavy metals, chromium is an important environmental pollutant, mainly concentrated in areas of intense anthropogenic pressure. The effect of potassium dichromate on Lemna minor populations was tested using the growth inhibition test. Cyto-histological and physiological analyses were also conducted to aid in understanding the strategies used by plants during exposure to chromium. Treatment with potassium dichromate caused a reduction in growth rate and frond size in all treated plants and especially at the highest concentrations. At these concentrations the photosynthetic pathway was also altered as shown by the decrease of maximum quantum yield of photosystem II and the chlorophyll b content and by the chloroplast ultrastructural modifications. Starch storage was also investigated by microscopic observations. It was the highest at the high concentrations of the pollutant. The data suggested a correlation between starch storage and reduced growth; there was greater inhibition of plant growth than inhibition of photosynthesis, resulting in a surplus of carbohydrates that may be stored as starch. The investigation helps to understand the mechanism related to heavy metal tolerance of Lemna minor and supplies information about the behavior of this species widely used as a biomarker.

Use of octadecylrhodamine fluorescence dequenching to study vesicular stomatitis virus fusion with human aged red blood cells.

Human erythrocytes were separated into five fractions representing different age groups. In each group phospholipid inside-outside translocation was determined by quantitation of the amino phospholipids phosphatidylserine and phosphatidylethanolamine and their lyso-derivatives by thin layer chromatography. To assess the role of transbilayer phospholipid distribution in the recognition and fusion of vesicular stomatitis virus (VSV) and human aged erythrocytes, we monitored the fusion kinetics using the octadecylrhodamine dequenching assay. Fusion of VSV with each single group of red blood cells (RBC) was not detectable with the youngest cells (F1 group) but increased with RBC aging (F2-F5 groups). The same increase in fusion was observed with microvesicles generated from RBC in which aging was mimicked by incubating the cells with Ca2+ in the presence of the Ca2+ ionophore A23187. Conversion of the aminophospholipids to the trinitrophenyl derivative by reaction with trinitrobenzensulfonate completely inhibits fusion on ghosts in which aging was artificially induced by translocation of aminophospholipids in the outer leaflet (symmetric ghosts). These results indicate that RBC become susceptible to VSV fusion during aging and in all pathology related to the aging process.

Specific intra-tissue responses to manganese in the floating lamina of Trapa natans L.

Plant tolerance to heavy metals requires morpho-physiological mechanisms that are still poorly understood, especially in hydrophytes. This study focuses on the young floating lamina of the rhyzophyte Trapa natans exposed for 10 d to 130 microM Mn. The lamina has the ability to bioaccumulate Mn (> 3000 microg g(-1)). X-ray microanalysis of Mn cellular distribution revealed accumulation in the upper epidermis, in the first palisade layer, and in the idioblasts of the spongy tissue, which were shown with electron microscopy to contain osmiophilic vacuolar deposits, also observed to a minor extent in the control leaves. On the basis of biochemical and histochemical tests, these deposits were attributed to phenolic compounds that were probably able to chelate Mn. Net photosynthesis, photosynthetic pigments, room temperature microspectrofluorimetric analyses, and ultrastructural studies of plastids were performed to evaluate the status of the photosynthetic apparatus. A greater development of thylakoid membranes was observed in plastids of the second palisade and spongy tissue, which, however, did not accumulate Mn. Only the spongy tissue experienced inadequate assembly of PS II, but this did not significantly influence the photosynthetic yield of the whole lamina. It was concluded that T. natans can optimise productivity in the presence of Mn by means of specific intra-tissue responses within the framework of the floating lamina.

A new monoclonal antibody to an age sensitive band 3 transmembrane segment.

The appearance of band 3 structural modifications related to aging could be evidenced by means of monoclonal antibodies against senescence antigen. Hence in the attempt to provide an immunological marker of erythrocyte aging, we raised a monoclonal antibody against native band 3 (B6 MoAb), which seems to detect differences in the band 3 molecule from erythrocytes of different ages separated by density gradient. Densitometric evaluation of immunoblotting patterns indicates that the in vivo aging is associated with band 3 monomer degradation. The Percoll separated fractions show a significant increase of those proteolytic fragments that bind the B6 antibody. Finally, protease digestions of unsealed membrane ghosts have been performed to test the binding site of the B6 antibody on the band 3 molecule. The data show that the B6 antibody binds a 19 KDa chymotryptic-tryptic fragment which corresponds to a segment of the looped membrane domain whose steric structure appears to be sensitive to age.

Clinical application of prismatic lenses in the rehabilitation of neglect patients. A randomized controlled trial.

BACKGROUND: Many studies reveal that neglect is a major cause of disability in stroke patients, and two months from onset neglect is still present in approximately 50% of individuals with a right brain lesion. Among the various methods of neglect rehabilitation, we have turned our attention to the prism adaptation treatment, developed by Rossetti in 1998. This treatment uses prismatic lenses, which produce a deviation of the fixation point of the visual field of 10 degrees to the right, 5 degrees below the coordinates of reference resulting from neglect. AIM: To set out the possible effectiveness of less powerful lenses, we studied the response of a group of neglect patients treated with prismatic lenses that produce a deviation of the fixation point of only 5 degrees to the right, comparing them with a group of patients receiving placebo lenses. DESIGN: Randomized controlled trial. SETTING: Outpatients. POPULATION: The study involved 29 patients with left visual neglect. METHODS: All patients were assessed with a battery of seven visual-spatial tests. All patients were randomized by the pilot center and assigned to two different groups: "A" treated with pointing exercises and prismatic lenses of 5° to the right; "B" treated with pointing exercises and neutral lenses. Each group was treated with 5 rehabilitation sessions, lasting about 30 minutes each, from Monday to Friday for one week in the morning, by the same investigator, in each center. CONCLUSION: The results showed that the prismatic lenses of only five degrees, used for the study, did not contribute to the variation in performance. Thus, this deviation of the fixation point of the visual field to the right is not sufficient to create a therapeutic effect. The improvement observed within the two groups, seems likely to be correlated with the pointing exercises, which force the subject to perform a visuomotor task with the healthy arm also in the neglected side. CLINICAL REHABILITATION IMPACT: We believe that in order to carry out an effective treatment with prismatic lenses they must have a grade of at least 20 prism diopters. Lower grades are unable to determine an effect. Finally, because of the severe impact of neglect on the work of the rehabilitation team, and since our data shows that only five sessions are sufficient to demonstrate a change in performance, we believe that it is appropriate to use this method, especially in the acute phase of the disease.

Responses of Trapa natans L. floating laminae to high concentrations of manganese.

The present study focuses on the responses of floating laminae of the Mn-tolerant hydrophyte Trapa natans L. to 1 mM Mn and their ability to accumulate the metal. Studies were carried out first on young floating laminae belonging to the second verticil of 30-day-old plants which originated from fruits that had been maintained in a 1 mM Mn-treated environment and again on the young floating laminae after 10 days of further treatment with 1 mM Mn. Mn storing was observed from the first days after germination, but only 10-day-treated laminae showed the capability to hyperaccumulate the element inside specialised cells (>20000 microg/g [dry weight]). Electron microscopy and the Folin-Ciocalteu reaction for phenolics revealed deposits of chelated material inside vacuoles of the first palisade layer and of idioblasts in the spongy tissue. X-ray microanalysis indicated that the deposits were Mn chelated with phenolic compounds. Numerous trichomes were observed at the lower epidermis of 10-day-treated laminae. They were rich in phenolics and characterised by Mn concretions at their base. As they are associated with a high concentration of the metal in culture water and sediments, trichomes may constitute a morphological differentiation for the secretion of Mn-chelating molecules into the culture water, as a probable "avoidance" mechanism. Finally, monitoring of the photosynthetic apparatus showed that photosynthetic function was not impaired, though differences in development occurred.

Modulations of the thylakoid system in snow xanthophycean alga cultured in the dark for two months: comparison between microspectrofluorimetric responses and morphological aspects.

The response of the plastid was studied, with a special emphasis on thylakoid structure and function, in a snow filamentous xanthophycean alga (Xanthonema sp.) incubated in darkness for two months. Microspectrofluorimetric analyses were performed on single living cells to study the variations in the assembly of the chlorophyll-protein complexes of photosystem II, in comparison with cells grown in light. In parallel, changes in micro- and submicroscopic plastid morphology and in photosynthetic pigment content were monitored. Throughout the experiment, the lamellar architecture of thylakoids in the alga was relatively well preserved, whereas photosystem II underwent disassembly and degradation triggered by prolonged darkness. Conversely, the light-harvesting complex of photosystem II proved to be relatively stable for long periods in darkness. Moreover, a role of the peripheral antennae in determining thylakoid arrangement in xanthophycean algae is implied. Although the responses observed in Xanthonema sp. can be considered in terms of acclimation to darkness, the progressive destabilisation of the light-harvesting complex of photosystem II testifies to incipient ageing of the cells after 35 days.

Adaptive modifications of the photosynthetic apparatus in Euglena gracilis Klebs exposed to manganese excess.

Asynchronous cultures of wild-type Euglena gracilis were tested for their morphophysiological response to 10 mM MnSO4. Growth was only moderately slowed (15%), while oxygen evolution was never compromised. Inductively coupled plasma analyses indicated that the Mn cell content doubled with respect to controls, but no signs of localised accumulation were detected with X-ray microanalysis. Evident morphological alterations were found at the plastid level with transmission electron microscopy and confocal laser scanning microscopy. An increase in the plastid mass, accompanied by frequent aberrations of chloroplast shape and of the organisation of the thylakoid system, was observed. These aspects paralleled a decrease in the molar ratio of chlorophyll a to b and an increase in the fluorescence emission ratio of light-harvesting complex II to photosystem II, the latter evaluated by in vivo single-cell microspectrofluorimetry. These changes were observed between 24 and 72 h of treatment. However, the alterations in the pigment pattern and photosystem II fluorescence were no longer observed after 96 h of Mn exposure, notwithstanding the maintenance of the large plastid mass. The response of the photosynthetic apparatus probably allows the alga to limit the photooxidative damage linked to the inappropriately large peripheral antennae of photosystem II. On the whole, the resistance of Euglena gracilis to Mn may be due to an exclusion-tolerance mechanism since most Mn is excluded from the cell, and the small amount entering the organism is tolerated by means of morphophysiological adaptation strategies, mainly acting at the plastid level.

Engineered liposomes and virosomes for delivery of macromolecules.

In order to utilize virosomes or proteoliposomes for the delivery of drugs or macromolecules to specific pathologic target cells we elaborated a system to shuttle drugs to solid tissue (liver) as well as to the macrophages, a crucial cellular compartment of the immune system. Using virosomes prepared from the P3HR1 strain of Epstein-Barr virus, we demonstrated that these particles fused with human hepatocarcinoma cell line Li7A and therefore might be used as drug vectors. Furthermore, we report that proteoliposomes prepared by reconstituting in a cocktail of phosphatidylserine-phosphatidylcholine the anion transporter band 3 protein markedly increased the phagocytic activity of macrophages in culture. This could represent a new device to be used as a drug delivery system to enhance specific macrophagic functions.

Oxidative erythrocyte membrane damage in hereditary spherocytosis.

The occurrence, in Hereditary Spherocytosis, of an oxidative damage to red blood cell membranes was studied by "in vitro" treatment of the erythrocytes with tert-butylhydroperoxide, methylene blue, or phenylhydrazine. Spherocytes were found to be more sensitive than normal erythrocytes to the action of these drugs. Tert-butylhydroperoxide caused a more intense lipid peroxidation as well as more extensive membrane protein alterations, namely spectrin degradation, formation of high molecular weight aggregates, and globin binding to the membrane. Marked spectrin degradation was also induced by methylene blue and by phenylhydrazine, which differed from each other for their effects on the generation of membrane-bound globin and of intermediate proteolysis products. Spectrin appeared therefore to be, in Hereditary Spherocytosis, a highly sensitive target to oxidative stress, a phenomenon which may, also "in vivo", increase the rate of spectrin loss thus enhancing erythrocyte fragility.

Mini-Mental State Examination (MMSE): sensitivity in an Italian sample of patients with dementia.

The sensitivity of the Mini-Mental State Examination (MMSE) was assessed in a sample of patients with dementia of the Alzheimer type or vascular dementia. The MMSE identified the majority of pts with diffuse cognitive impairment but did not discriminate between the two types of dementia. If failed to detect mild deterioration or forms in which only some cognitive functions were impaired. The test is therefore not sufficient for distinguishing deteriorated from non deteriorated pts, although it is still useful in mass screening or for a quick assessment of deterioration in the course of clinical neurological examination.

In situ polymerization into porous ceramics: a novel route to tough biomimetic materials.

A hydroxyapatite-based biomimetic composite, which is henceforth referred to as a synthetic bony material with high toughness characteristics, was prepared. It was obtained from a hydroxyapatite (HAp) skeleton with a relative porosity fraction of approximately 32 vol %, prepared by cold-isostatic-press compaction, followed by a sintering process, leading to a hydroxyapatite structure containing percolated submicrometer porosity channels. The percolated pores were infiltrated with a liquid mixture of epsilon-caprolactam monomer and an initiator, before homogeneous in situ polymerization to 6-nylon within the fully percolated pore structure was induced thermally. The final composite consisted of a dense interpenetrated hydroxyapatite/6-nylon network in a fraction approximately 68/30 vol %. The work of fracture value of the hybrid composite was found to be comparable with those found in two natural materials (bovine femur and nacre), which were also investigated under the same testing conditions.

Isolation and purification of a major allergen from Parietaria officinalis pollen.

A major allergen of Parietaria officinalis, a species responsible for a large number of respiratory allergies in Mediterranean areas, has been identified and characterized. This allergen (Pol) was found in the fraction which precipitates between 70 and 100% ammonium sulphate saturation. Pol showed a molecular weight of 15,000 daltons as determined by SDS-PAGE and HPLC. The pI of Pol was in the pH region 4-6, IEF showing four major bands. Two major bands were shown by CIE, CRIE and immunoblotting; major contaminants or aggregates were also revealed by the latter technique and by HPLC. Pol showed an allergic specific activity 2 times higher than the crude extract; moreover it was shown to be a major allergen since it inhibited 29 out of 30 sera from allergic patients sensitive to P. officinalis.