Phosphatidylserine Supplementation as a Novel Strategy for Reducing Myocardial Infarct Size and Preventing Adverse Left Ventricular Remodeling

Phosphatidylserines are known to sustain skeletal muscle activity during intense activity or hypoxic conditions, as well as preserve neurocognitive function in older patients. Our previous studies pointed out a potential cardioprotective role of phosphatidylserine in heart ischemia. Therefore, we investigated the effects of phosphatidylserine oral supplementation in a mouse model of acute myocardial infarction (AMI). We found out that phosphatidylserine increases, significantly, the cardiomyocyte survival by 50% in an acute model of myocardial ischemia-reperfusion. Similar, phosphatidylserine reduced significantly the infarcted size by 30% and improved heart function by 25% in a chronic model of AMI. The main responsible mechanism seems to be up-regulation of protein kinase C epsilon (PKC-ε), the main player of cardio-protection during pre-conditioning. Interestingly, if the phosphatidylserine supplementation is started before induction of AMI, but not after, it selectively inhibits neutrophil’s activation, such as Interleukin 1 beta (IL-1β) expression, without affecting the healing and fibrosis. Thus, phosphatidylserine supplementation may represent a simple way to activate a pre-conditioning mechanism and may be a promising novel strategy to reduce infarct size following AMI and to prevent myocardial injury during myocardial infarction or cardiac surgery. Due to the minimal adverse effects, further investigation in large animals or in human are soon possible to establish the exact role of phosphatidylserine in cardiac diseases.     

Conductivity Tuning via Doping with Electron Donating and Withdrawing Molecules in Perovskite CsPbI3 Nanocrystal Films

Doping of semiconductors enables fine control over the excess charge carriers, and thus the overall electronic properties, crucial to many technologies. Controlled doping in lead‐halide perovskite semiconductors has thus far proven to be difficult. However, lower dimensional perovskites such as nanocrystals, with their high surface‐area‐to‐volume ratio, are particularly well‐suited for doping via ground‐state molecular charge transfer. Here, the tunability of the electronic properties of perovskite nanocrystal arrays is detailed using physically adsorbed molecular dopants. Incorporation of the dopant molecules into electronically coupled CsPbI₃ nanocrystal arrays is confirmed via infrared and photoelectron spectroscopies. Untreated CsPbI₃ nanocrystal films are found to be slightly p‐type with increasing conductivity achieved by incorporating the electron‐accepting dopant 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F₄TCNQ) and decreasing conductivity for the electron‐donating dopant benzyl viologen. Time‐resolved spectroscopic measurements reveal the time scales of Auger‐mediated recombination in the presence of excess electrons or holes. Microwave conductance and field‐effect transistor measurements demonstrate that both the local and long‐range hole mobility are improved by F₄TCNQ doping of the nanocrystal arrays. The improved hole mobility in photoexcited p‐type arrays leads to a pronounced enhancement in phototransistors.     

An analytical approach to bistable biological circuit discrimination using real algebraic geometry

Biomolecular circuits with two distinct and stable steady states have been identified as essential components in a wide range of biological networks, with a variety of mechanisms and topologies giving rise to their important bistable property. Understanding the differences between circuit implementations is an important question, particularly for the synthetic biologist faced with determining which bistable circuit design out of many is best for their specific application. In this work we explore the applicability of Sturm''s theorem—a tool from nineteenth-century real algebraic geometry—to comparing ‘functionally equivalent’ bistable circuits without the need for numerical simulation. We first consider two genetic toggle variants and two different positive feedback circuits, and show how specific topological properties present in each type of circuit can serve to increase the size of the regions of parameter space in which they function as switches. We then demonstrate that a single competitive monomeric activator added to a purely monomeric (and otherwise monostable) mutual repressor circuit is sufficient for bistability. Finally, we compare our approach with the Routh–Hurwitz method and derive consistent, yet more powerful, parametric conditions. The predictive power and ease of use of Sturm''s theorem demonstrated in this work suggest that algebraic geometric techniques may be underused in biomolecular circuit analysis.     

Aspect ratio dependence of the elastic properties of ZnO nanobelts

The Young's modulus of ZnO nanobelts was measured with an atomic force microscope by means of the modulated nanoindentation method. The elastic modulus was found to depend strongly on the width-to-thickness ratio of the nanobelt, decreasing from about 100 to 10 GPa, as the width-to-thickness ratio increases from 1.2 to 10.3. This surprising behavior is explained by a growth-direction-dependent aspect ratio and the presence of stacking faults in nanobelts growing along particular directions.     

Prevalence of 25(OH) vitamin D insufficiency and deficiency in chronic kidney disease stage 5 patients on hemodialysis

Little is known about the magnitude of vitamin D deficiency in patients with stage 5 chronic kidney disease (CKD-5) on hemodialysis (HD). In the present study, we examined the prevalence of vitamin D deficiency in patients with CKD-5 undergoing HD, evaluating the relationship between calcidiol levels with other parameters of mineral metabolism, nutrition/inflammation, functional capacity (FC), and sunlight exposure. Serum 25(OH) vitamin D levels were evaluated in 84 stable patients on chronic HD not receiving vitamin D supplements, with a mean age 58.9+/-16.6 years, during the month of September (end of winter in the southern hemisphere). 25(OH) vitamin D serum levels, intact PTH (iPTH), as well as serum albumin, calcium, phosphorus, and alkaline phosphatase were analyzed in fasting samples. Similarly, protein catabolic rate (PCR) and body mass index (BMI) were determined as nutritional parameters. Functional capacity according to the Karnofsky index, and sunlight exposure were also analyzed. In this study, we considered adequate vitamin D levels those above 30 ng/mL (U.S.A. National Kidney Foundation DOQI Guidelines), vitamin D insufficiency when levels were between 15 and 30 ng/mL, and vitamin D deficiency when levels were below 15 ng/mL. The mean 25(OH) D levels were significantly higher in men than in women (28.6 vs. 18.9 ng/mL; p=0.001). Vitamin D insufficiency was found in 53.5% of the patients (n=45) and vitamin D deficiency in 22.6% (n=19). In the univariate analysis, there were no correlations between 25(OH) D levels with age, iPTH, calcium, or phosphorus. There were positive correlations between serum 25(OH) D levels and degrees of sunlight exposure (R=0.55; p<0.0001), serum creatinine (r=0.38; p<0.001), serum albumin (r=0.22; p=0.04), and a negative correlation with BMI (r=-0.26; p=0.01). In the multiple regression analysis, only sunlight exposure (B=0.361), BMI (B=-0.23), and gender (B=-0.27) were significantly associated with 25(OH) D levels. Patients with FC 1 to FC 2 (n: 70%, 83.3%) had significantly higher 25(OH) D serum levels compared with FC 3 to FC 4 patients (n: 14%, 16.6%): 25.9 vs. 17.1 ng/mL (p=0.03). These results indicate that vitamin D insufficiency/deficiency is highly prevalent (76.1%) at the end of winter, in stage 5 CKD patients on HD, and lower values seem to be related to decreased sunlight exposure, female gender, increased BMI, and worse functional class.     

Imbalance between phytoplankton production and bacterial carbon demand in relation to mucilage formation in the Northern Adriatic Sea

Spatial and temporal changes in phytoplankton production and bacterial C demand were investigated at four stations in the Northern Adriatic Sea over 3 years. The effect of the Po River plume was observed at the western stations; in particular, the northernmost one (B06) showed the highest values of primary production, both as hourly peaks (up to 14 mg C m(-3) h(-1)) and daily water column integrated values (up to 740 mg C m(-2) day(-1)), the southern station (C04) was only sporadically influenced and did not differ significantly from the easternmost ones (C12 and B13), where the lowest TPP values were recorded (around 1 mg C m(-3) h(-1)). In this study the first in situ data are reported on short-term phytoplankton C extra cellular release in the Northern Adriatic Sea. At every station a considerable percentage of primary production (PER>20% as an average, with peaks of up to 70%) was released as dissolved organic carbon. In particular, an association of fairly high PER (>10%) and specific production (Pb>10 mg C mg chl(-1) h(-1)) was observed from spring to summer, when the mucilage phenomenon usually starts. This result might suggest the presence of an uncoupling between photosynthesis and growth, probably related with nutrient availability, which would be responsible for a high production of extra cellular organic carbon. Phytoplankton primary production and bacterial carbon production were closely related and bacterial C production accounted, on average, for a higher percentage of primary production than the values typically reported in the literature on aquatic environments. The flow of organic matter from phytoplankton to bacteria seems to satisfy the bacterial carbon demand during most of the spring and summer, at least in the upper water layers. However, during the summer, there is evidence that BCD sometimes exceeds the amount of C produced by phytoplankton. Neither phytoplankton nor bacterial production showed significant differences over the relevant years, and their absolute values did not change when comparing periods with or without mucilage. However, there were indications of an uncoupling between phytoplankton photosynthesis and growth and of a shift from an autotrophic to a heterotrophic metabolism, especially during the spring and summer period when mucilage might occur.     

Hydrodeoxygenation of Phenol on Beta Zeolite Catalysts

Biomass is considered the largest renewable energy source and an important alternative for biofuel production. The fast pyrolysis of biomass is an economical and advantageous to get bio-oil. However, bio-oil has a large amount of oxygenated compounds and needs upgrade. The catalytic process of HDO （hydrodeoxygenation） is the most efficient way to remove oxygen from the bio-oil. In this paper, it was studied the HDO phenol （300 ℃ and 35 atm） on catalysts based on cobalt or copper oxides supported on HBeta zeolite. The catalysts were characterized by XRD （X-ray diffraction）, FTIR （infrared spectroscopy） and NH3-TPD （desorption of ammonia）. The results showed the presence of CO304 （cobalt oxide） and CuO （copper oxide）. The measurements showed the presence of acid sites weak, moderate and strong and that the impregnation of the metal oxide modifying the acidity of the support. The results showed the following order HDO conversion： CoHBeta 〉 CuHBeta 〉 HBeta. The presence of the cobalt or copper catalysts contributes to the increase in conversion due to hydrogenation. All catalysts were selective to benzene, but only the impregnated catalysts showed selectivity to cyclohexane and cyclohexene.     

Extension of Tosèla cheese shelf-life using non-starter lactic acid bacteria

Six strains of non-starter lactic acid bacteria (NSLAB) were used to extend the shelf-life of the fresh cheese Tosèla manufactured with pasteurised cows’ milk. The acidification kinetics of three Lactobacillus paracasei, one Lactobacillus rhamnosus and two Streptococcus macedonicus were studied in synthetic milk medium. Lb. paracasei NdP78 and NdP88 and S. macedonicus NdP1 and PB14-1 showed an interesting acidifying capacity and were further characterised for growth in UHT milk and production of antimicrobial compounds. Lb. paracasei NdP78 and S. macedonicus NdP1 grew more than 2 log cycles in 6 h. Lb. paracasei NdP78 was also found to produce a bacteriocin-like inhibitory substance (BLIS) active against Listeria monocytogenes. The four NSLAB strains (singly or in combination) were used to produce experimental pilot-scale cheeses which were compared by a panel. The cheese manufactured with the mixed culture Lb. paracasei NdP78 - S. macedonicus NdP1 was the most appreciated for its sensory properties. The cheeses produced at factory-scale showed higher concentrations of lactobacilli (7.90 log CFU/g) and streptococci (6.10 log CFU/g), but a lower development of coliforms (3.10 log CFU/g) and staphylococci (2.78 log CFU/g) than control cheese (4.86, 4.89, 4.93 and 5.00 log CFU/g of lactobacilli, streptococci, coliforms and staphylococci, respectively) processed without NSLAB addition. The food pathogens Salmonella spp. and Listeria monocytogenes were never detected. The dominance of the species inoculated was demonstrated by denaturing gradient gel electrophoresis (DGGE), whereas strain recognition was evaluated by randomly amplified polymorphic DNA (RAPD)-PCR. From the results obtained, Lb. paracasei NdP78 and S. macedonicus NdP1 were able to persist during the storage of Tosèla cheese and their combination influenced positively the sensory characteristics and shelf-life of the final product.     

Asian herbal‐tobacco cigarettes: “not medicine but less harmful”?

Objective

To describe the development and health claims of Asian herbal‐tobacco cigarettes.

Methods

Analysis of international news sources, company websites, and the transnational tobacco companies'' (TTC) documents. PubMed searches of herbs and brands.

Results

Twenty‐three brands were identified, mainly from China. Many products claimed to relieve respiratory symptoms and reduce toxins, with four herb‐only products advertised for smoking cessation. No literature was found to verify the health claims, except one Korean trial of an herb‐only product. Asian herbal‐tobacco cigarettes were initially produced by China by the 1970s and introduced to Japan in the 1980s. Despite initial news about research demonstrating a safer cigarette, the TTC analyses of these cigarettes suggest that these early products were not palatable and had potentially toxic cardiovascular effects. By the late 1990s, China began producing more herbal‐tobacco cigarettes in a renewed effort to reduce harmful constituents in cigarettes. After 2000, tobacco companies from Korea, Taiwan, and Thailand began producing similar products. Tobacco control groups in Japan, Taiwan, and Thailand voiced concern over the health claims of herbal‐tobacco products. In 2005, China designated two herbal‐tobacco brands as key for development.

Conclusion

Asian herbal‐tobacco cigarettes claim to reduce harm, but no published literature is available to verify these claims or investigate unidentified toxicities. The increase in Asian herbal‐tobacco cigarette production by 2000 coincides with the Asian tobacco companies'' regular scientific meetings with TTCs and their interest in harm reduction. Asia faces additional challenges in tobacco control with these culturally concordant products that may discourage smokers from quitting.     

Field-induced phase transition and relaxor character in submicrometer-structured lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 piezoceramics at the morphotropic phase boundary

Submicrometer-structured (Bi(0.5)Na(0.5))(0.94)Ba(0.06)TiO(3) ceramics ((G) < 720 nm) from nanopowders were studied. The real part of the optimum room temperature set of piezoelectric coefficients obtained from resonances of the BNBT6 dense ceramic disks and shear plates [d(31) = (-37 + 1.33i) pC·N(-1), d(15) = (158.3 - 8.31i) pC·N(-1), k(t) = 40.4%, k(p) = 26.8%, and k(15) = 40.2%] and d(33) (148 pC·N(-1)) can be compared with the reported properties for coarse-grained ceramics. Shear resonance of thickness-poled plates is observed at T = 140°C. Permittivity versus temperature curves of poled samples show relaxor character up to T(i) = 230°C on heating and T(i) = 210°C on cooling of the depoled samples. The phase transition from the room-temperature ferroelectric (FE) to a low-temperature non-polar at zero field (LTNPZF) phase can be observed as a sharp jump in ε(δ)(33)'(T) curves or, as the degree of poling decreases, as a soft change of slope of the curves at T(FE-LTNPZF) = T(d) = 100°C. This dielectric anomaly is not observed on cooling of depoled samples, because the FE phase is field-induced. The observed macroscopic piezoelectric activity above T(d) is a consequence of the coexistence of nanoregions of the FE phase in the interval between T(FE-LTNPZF) and T(i).