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Tammann&rsquo, s two-stage crystal-nuclei-development method is applied for analysis of the thermal stability of homogenously formed crystal nuclei of poly(butylene isophthalate) (PBI) as well as their possible reorganization on transferring them to the growth temperature, using fast scanning chip calorimetry. Crystal nuclei were formed at 50 &deg, C, that is, at a temperature only slightly higher than the glass transition temperature, and developed to crystals within a pre-defined time at the growth temperature of 85 &deg, C. The number of nuclei, overcritical at the growth temperature, was detected as a function of the transfer-conditions (maximum temperature, heating rate) by evaluation of the developed crystal fraction. For different size-distributions of crystal nuclei, as controlled by the nucleation time, there is detected distinct reduction of the nuclei number on heating to maximum temperatures higher than about 90 to 110 &deg, C, with the latter value holding for longer nucleation time. Longer nucleation allows for both increasing the absolute nuclei number and generation of an increased fraction of larger nuclei. Heating at 1000 K/s to 140&ndash, 150 &deg, C causes &ldquo, melting&rdquo, of even the most stable nuclei. While direct transfer of crystal nuclei from the nucleation temperature (50 &deg, C) to the growth temperature (85 &deg, C) reveals negligible effect of the transfer-heating rate, in-between heating to higher temperatures is connected with distinct nuclei-reorganization above 85 &deg, C on heating slower than 1000&ndash, 10.000 K/s. The performed study not only provides specific valuable information about the thermal characteristics of crystal nuclei of PBI but also highlights the importance of proper design of Tammann&rsquo, s nuclei development experiment for analysis of nuclei numbers. With the evaluation of critical rates of temperature-change for suppression of non-isothermal formation of both nuclei and crystals, the kinetics of crystallization of the slow crystallizing PBI is further quantified.

La crescente attenzione dei consumatori per gli alimenti funzionali ha stimolato le ricerche su nuovi tipi di pasta ottenuti con ingredienti in grado di migliorarne l’attività antiossidante, il profilo amminoacidico o il contenuto di acidi grassi polinsaturi e fibre, con risultati, però, non sempre soddisfacenti a causa di alterazioni delle proprietà tecnologiche e sensoriali della pasta (consistenza, tenuta alla cottura, odori e sapori inusuali). La crusca di grano duro contiene numerosi composti bioattivi, tra cui fenoli, carotenoidi e tococromanoli, che possono essere estratti con tecnologie green e reintegrati nell’impasto per ottenere prodotti con caratteristiche simili alla pasta tradizionale ma con elevata attività antiossidante. Questa strategia, definibile “da grano a grano”, è stata utilizzata con successo impiegando estratti idrofili o lipofili di crusca. In questo lavoro i risultati conseguiti sino ad ora sono riassunti e criticamente revisionati. The increasing interest of consumers towards functional foods has induced researches aimed to obtain new pasta types by using ingredients able to improve antioxidant activity, amino acid or fatty acid profile, and soluble fiber content. However, the results have not been satisfactory in all cases, due to frequently observed anomalous odor and taste or decreased consistency. Durum wheat bran contains several bioactive compounds, such as phenolics, carotenoids, and tocochromanols, which can be extracted by means of green technologies. To preserve as much as possible the sensory features of pasta, an interesting strategy, that can be referred to as “from wheat to wheat”, is to enrich and functionalize pasta with durum wheat bran extracts. The aim of this work has been to resume and review the results obtained by the studies aimed to obtain functional pasta, focusing in particular on those based on this strategy.

Peach (Prunus persica L.) fruits contain several health-promoting phytochemicals. Among these, carotenoids, in addition to being involved in determining flesh color, play a relevant role in cell protection against oxidative stress. Nevertheless, antioxidant activity (AA) of peach carotenoids so far has not been investigated in as much detail as phenols. In the present study, for the first time, AA of peach carotenoid extracts was evaluated using the innovative lipoxygenase/4-nitroso-N,N-dimethylaniline (LOX/RNO) method, able to simultaneously detect different antioxidant mechanisms and synergistic antioxidant interactions, as well as using the well-known ORAC and TEAC assays. In particular, extracts were obtained from fruits collected in S4 development stage from two yellow-fleshed (Armking and Redhaven) and three white-fleshed (Silverking, Caldesi 2000, IFF331) varieties. The LOX/RNO method gave high AA values (10-150 μmol eq. Trolox/g f.w.), about 85-1900-fold higher than ORAC and TEAC methods. Moreover, the ratio between AA values, measured by the LOX/RNO method, of yellow- and white-fleshed peaches resulted equal to 14, but only 2.6 and 3.6 for ORAC and TEAC, respectively. Results of this study indicate that the LOX/RNO method, measuring high AA values and easily discriminating among samples, is an advisable tool to assess the AA of the carotenoid component in peach., Advances in Horticultural Science, Vol 29 No 2-3 (2015)

Pro-inflammatory cytokines, in addition to their role in host defence, can be considered a disease mediator; therefore, a reduction in cytokine synthesis or its effects is becoming a target of many diseases. Interleukin-6 (IL-6) is a pro-inflammatory cytokine that could play a role in several clinical problems related to dialysis treatment. Biological activities of IL-6 could be modulated by two soluble circulating receptors, namely sIL-6R and sgp130. sIL-6R can enhance the inflammatory effects of IL-6 and; therefore, is an "agonistically" acting molecule. On the contrary, sgp130 efficiently binds the IL-6/sIL-6R complex with "antagonistic" effects. In this study we evaluated sgp130 release by peripheral blood mononuclear cells (PBMC) harvested from 10 healthy controls (CON) and 11 end-stage renal disease (ESRD) patients undergoing renal dialysis therapy RDT) with cellulosic hemophan membrane (HD). We also evaluated gp130 gene expression by reverse transcriptase polymerase chain reaction (RT-PCR). gp130 is the membrane bound receptor of IL-6 that could be proteolytically cleaved to generate soluble sgp130. Our results demonstrated that HD. at basal conditions, showed a higher release of sgp130 as compared with CON. We also demonstrated by RT-PCR at basal conditions a higher gene expression of gp130 in HD, as compared with CON. These results took place in the absence of any mitogenic stimulation and suggest that in HD patients an inflammatory subclinical status increases sgp130 release. The results obtained after lipopolysaccharide (LPS) stimulation confirm the role of inflammation on the increased release of sgp130 in HD patients.

Soluble gp130 (sgp130) is a soluble circulating receptor of IL-6 with "antagonistic" biologic activity. It is generated independently by either shedding of the extracellular domain of membrane gp130 or alternative mRNA splicing. This study was addressed to clarify the mechanisms underlying sgp130 synthesis and release in patients who undergo regular dialysis treatment (RDT) using dialytic membranes with different biocompatibility. Two groups of RDT patients were enrolled: 11 patients who were treated with cellulosic membranes (C) and 10 patients who were treated with synthetic membranes (S). Ten healthy subjects constituted the control group. Serum samples and peripheral blood mononuclear cells (PBMC) were harvested in all groups (before dialysis in RDT patients). PBMC were cultured for 24 h in the absence or presence of LPS. The serum levels of sgp130 were significantly higher in C group than in control and S patients (C, 603.1 +/- 89.9; control, 396 +/- 49.5; S, 423.4 +/- 27.7 ng/ml; P < 0.01). PBMC from C patients, in the absence of any mitogenic stimulation, released a significantly greater amount of sgp130 as compared with S and control groups (C, 532.6 +/- 161.2; S, 332.4 +/- 148.6; control, 341.4 +/- 125.4 pg/ml; P < 0.01). The sgp130 release was positively correlated with the release of both IL-6 (r = 0.336, P < 0.05) and sIL-6R receptor (r = 0.324, P < 0.05). A significantly higher gp130 gene expression was also observed in unstimulated PBMC from C patients when compared with control and S groups. It is interesting that the expression of the 85-bp exon characteristic of the alternative splicing mRNA for sgp130 was low in all groups. Finally, confocal microscopy analysis showed an increased expression of gp130 on cell surface in unstimulated PBMC from C patients as compared with control and S groups. Our results demonstrate that in patients on RDT with C membranes, the synthesis and release of sgp130 "antagonistic" receptor is significantly increased. This release is seemingly due to a shedding of membrane-bound gp130 receptor. The increased sgp130 release may partially counteract the inflammatory effects caused by IL-6.

Poly(glycolic acid) (PGA) and a series of novel random copolymers of PGA containing 2-hydroxyisobutyrric acid (PGAPHIB) (HIB unit content from 1.5 to 7.4 mol %) were synthesized and characterized in terms of chemical structure and molecular weight. Afterward, the polyesters were examined by thermogravimetric analysis, differential scanning calorimetry, and X-ray diffraction techniques. The copolymers, which displayed a better thermal stability than PGA, at room temperature appeared as semicrystalline materials: the main effect of copolymerization was a lowering in the amount of crystallinity and a decrease of the melting temperature with respect to homopolymer PGA. Baur's equation described well the T(m)-composition data. X-ray diffraction measurements allowed the identification of the PGA crystalline structure in all cases. After melt quenching, semicrystalline samples were obtained with the exception of PGAPHIB7.4 copolymer. The introduction of HIB units decreased the crystallization rate compared with pure PGA. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1901-1910, 2010