Dietary supplementation with Bacillus mixture modifies the intestinal ecosystem of weaned piglets in an overall beneficial way.

AIMS: This study was conducted to investigate the effects of dietary supplementation with a mixture of Bacillus, which serves as an alternative of antibiotics on the intestinal ecosystem of weaned piglets. METHODS AND RESULTS: We randomly assigned 120 piglets to three groups: a control group (a basal diet), a probiotics group (a basal diet supplemented with 4 × 109  CFU per gram Bacillus licheniformis-Bacillus subtilis mixture; BLS mix), and an antibiotics group (a basal diet supplemented with 0·04 kg t-1 virginiamycin, 0·2 kg t-1 colistin and 3000 mg kg-1 zinc oxide). All groups had five replicates with eight piglets per replicate. On days 7, 21 and 42 of the trial, intestine tissue and digesta samples were collected to determine intestinal morphology, gut microbiota and bacterial metabolite composition, and the expression of genes related to the gut barrier function and inflammatory status. The results showed that the BLS mix decreased the jejunum crypt depth, while increased the ileum villus height and the jejunum and ileum villus height to crypt depth ratio. The BLS mix increased Simpson's diversity index in the gut microbiota and the relative abundances of o_Bacteroidetes and f_Ruminococcaceae, but decreased the relative abundances of Blautia and Clostridium. Dietary BLS mix supplementation also modified the concentration of several bacterial metabolites compared to the control group. In addition, BLS mix upregulated the expression level of E-cadherin in the colon and pro-inflammatory cytokines and TLR-4 in ileum and colon. Lastly, Spearman's rank-order correlation revealed a potential link between alterations in gut microbiota and health parameters of the weaned piglets. CONCLUSION: These findings suggest that dietary BLS mix supplementation modifies the gut ecosystem in weaned piglets. The potential advantages of such modifications in terms of intestinal health are discussed. SIGNIFICANCE AND IMPACT OF THE STUDY: Weaning is the most important transition period of piglet growth and development. This study showed that dietary supplementation of a probiotic mixture of Bacillus, an effective alternative of antibiotics, was beneficial in improving the intestinal ecosystem of weaned piglets.

Adsorption and superficial transport of oil on biological and bionic superhydrophobic surfaces: a novel technique for oil-water separation.

Superhydrophobicity is a physical feature of surfaces occurring in many organisms and has been applied (e.g. lotus effect) in bionic technical applications. Some aquatic species are able to maintain persistent air layers under water (Salvinia effect) and thus become increasingly interesting for drag reduction and other 'bioinspired' applications. However, another feature of superhydrophobic surfaces, i.e. the adsorption (not absorption) and subsequent superficial transportation and desorption capability for oil, has been neglected. Intense research is currently being carried out on oil-absorbing bulk materials like sponges, focusing on oleophilic surfaces and meshes to build membranes for oil-water separation. This requires an active pumping of oil-water mixtures onto or through the surface. Here, we present a novel passive, self-driven technology to remove oil from water surfaces. The oil is adsorbed onto a superhydrophobic material (e.g. textiles) and transported on its surface. Vertical and horizontal transportation is possible above or below the oil-contaminated water surface. The transfer in a bioinspired novel bionic oil adsorber is described. The oil is transported into a container and thus removed from the surface. Prototypes have proven to be an efficient and environmentally friendly technology to clean oil spills from water without chemicals or external energy supply. This article is part of the theme issue 'Bioinspired materials and surfaces for green science and technology (part 3)'.

Correction to: Polymyxin B causes DNA damage in HK-2 cells and mice.

In the original publication of the article, part of Fig. 6 is missing. The missing subpanels, Fig. 6c, d are given below.

Polymyxin B causes DNA damage in HK-2 cells and mice.

Increasing incidence of multidrug-resistant bacteria presents an imminent risk to global health. Polymyxins are 'last-resort' antibiotics against Gram-negative 'superbugs'; however, nephrotoxicity remains a key impediment in their clinical use. Molecular mechanisms underlying this nephrotoxicity remain poorly defined. Here, we examined the pathways which led to polymyxin B induced cell death in vitro and in vivo. Human proximal tubular cells were treated with polymyxin B (12.5-100 µM) for up to 24 h and showed a significant increase in micronuclei frequency, as well as abnormal mitotic events (over 40% in treated cells, p < 0.05). Time-course studies were performed using a mouse nephrotoxicity model (cumulative 72 mg/kg). Kidneys were collected over 48 h and investigated for histopathology and DNA damage. Notable increases in γH2AX foci (indicative of double-stranded breaks) were observed in both cell culture (up to ~ 44% cells with 5+ foci at 24 h, p < 0.05) and mice treated with polymyxin B (up to ~ 25%, p < 0.05). Consistent with these results, in vitro assays showed high binding affinity of polymyxin B to DNA. Together, our results indicate that polymyxin B nephrotoxicity is associated with DNA damage, leading to chromosome missegregation and genome instability. This novel mechanistic information may lead to new strategies to overcome the nephrotoxicity of this important last-line class of antibiotics.

Fog Collection on Polyethylene Terephthalate (PET) Fibers: Influence of Cross Section and Surface Structure.

Fog-collecting meshes show a great potential in ensuring the availability of a supply of sustainable freshwater in certain arid regions. In most cases, the meshes are made of hydrophilic smooth fibers. Based on the study of plant surfaces, we analyzed the fog collection using various polyethylene terephthalate (PET) fibers with different cross sections and surface structures with the aim of developing optimized biomimetic fog collectors. Water droplet movement and the onset of dripping from fiber samples were compared. Fibers with round, oval, and rectangular cross sections with round edges showed higher fog-collection performance than those with other cross sections. However, other parameters, for example, width, surface structure, wettability, and so forth, also influenced the performance. The directional delivery of the collected fog droplets by wavy/v-shaped microgrooves on the surface of the fibers enhances the formation of a water film and their fog collection. A numerical simulation of the water droplet spreading behavior strongly supports these findings. Therefore, our study suggests the use of fibers with a round cross section, a microgrooved surface, and an optimized width for an efficient fog collection.

Hierarchical Surface Architecture of Plants as an Inspiration for Biomimetic Fog Collectors.

Fog collectors can enable us to alleviate the water crisis in certain arid regions of the world. A continuous fog-collection cycle consisting of a persistent capture of fog droplets and their fast transport to the target is a prerequisite for developing an efficient fog collector. In regard to this topic, a biological superior design has been found in the hierarchical surface architecture of barley (Hordeum vulgare) awns. We demonstrate here the highly wettable (advancing contact angle 16° ± 2.7 and receding contact angle 9° ± 2.6) barbed (barb = conical structure) awn as a model to develop optimized fog collectors with a high fog-capturing capability, an effective water transport, and above all an efficient fog collection. We compare the fog-collection efficiency of the model sample with other plant samples naturally grown in foggy habitats that are supposed to be very efficient fog collectors. The model sample, consisting of dry hydrophilized awns (DH awns), is found to be about twice as efficient (fog-collection rate 563.7 ± 23.2 µg/cm(2) over 10 min) as any other samples investigated under controlled experimental conditions. Finally, a design based on the hierarchical surface architecture of the model sample is proposed for the development of optimized biomimetic fog collectors.

Electrolysed reduced water decreases reactive oxygen species-induced oxidative damage to skeletal muscle and improves performance in broiler chickens exposed to medium-term chronic heat stress.

1. The present study was designed to achieve a reduction of reactive oxygen species (ROS)-induced oxidative damage to skeletal muscle and to improve the performance of broiler chickens exposed to chronic heat stress. 2. Chickens were given a control diet with normal drinking water, or diets supplemented with cashew nut shell liquid (CNSL) or grape seed extract (GSE), or a control diet with electrolysed reduced water (ERW) for 19 d after hatch. Thereafter, chickens were exposed to a temperature of either 34°C continuously for a period of 5 d, or maintained at 24°C, on the same diets. 3. The control broilers exposed to 34°C showed decreased weight gain and feed consumption and slightly increased ROS production and malondialdehyde (MDA) concentrations in skeletal muscle. The chickens exposed to 34°C and supplemented with ERW showed significantly improved growth performance and lower ROS production and MDA contents in tissues than control broilers exposed to 34°C. Following heat exposure, CNSL chickens performed better with respect to weight gain and feed consumption, but still showed elevated ROS production and skeletal muscle oxidative damage. GSE chickens did not exhibit improved performance or reduced skeletal muscle oxidative damage. 4. In conclusion, this study suggests that ERW could partially inhibit ROS-induced oxidative damage to skeletal muscle and improve growth performance in broiler chickens under medium-term chronic heat treatment.

CYP3A genotypes in Bangladeshi tuberculosis patients.

The purpose of this study is to investigate the genotype and allelic frequencies of CYP3A in Bangladeshi Tuberculosis (TB) patients which may help for individualized drug dosing and improved therapeutics. Genotyping was done using the extracted genomic DNA from 90 TB patients followed by amplification of target alleles by Polymerase Chain Reaction (PCR). Amplified alleles were then digested by restriction enzymes followed by gel electrophoresis & sequencing to identify the targeted alleles namely CYP3A4*1B, CYP3A4*2, CYP3A4*4, CY3A4*5, CYP3A4*6, CYP3A4*10, CYP3A4*18, and CYP3A5*3. In TB patients, no samples were positive for CYP3A4*2, CYP3A4*4, CYP3A4*5, CYP3A4*6, CYP3A4*10, and CYP3A4*18 alleles. One sample was found to be heterozygous for CYP3A4*1B (1.11%). The wild homozygous (CYP3A5*1/*1) genotype frequency was 7.78%, the heterozygous (CYP3A5*1/*3) frequency was 42.22% and the homozygous mutant (CYP3A5*3/*3) frequency was 50% in Bangladeshi TB patients. The absence of the common polymorphic gene suggests that there will be no impact of CYP3A drug metabolizing enzymes on antituberculosis drugs.

Time course of ROS production in skeletal muscle mitochondria from chronic heat-exposed broiler chicken.

This study was designed to elucidate physiological changes of skeletal muscle mitochondria from broiler chickens (Gallus gallus) during chronic heat exposure. Chickens (19-day-old) were exposed to either constant heat stress (34 degrees C) or kept at control temperature (24 degrees C) for 14days. Mitochondrial ROS production for control group showed little changes during the experimental periods, whereas that for the heat-stressed group was increased after 3, 5 and 9days of heat exposure and returned to original levels at day 14. Mitochondrial membrane potential in state 4 for heat-stressed birds was higher than those of control birds after 3 and 5days, but was not at day 14. Mitochondrial oxygen consumption rate in state 3 was increased after 3 and 5days, and also returned to original levels by day 14. These results suggest that chronic heat stress induces increased ROS production in skeletal muscle mitochondria, probably via elevation of the membrane potential in state 4, resulting from enhanced oxygen consumption in the initial stage of heat exposure. These physiological changes were no longer observed at day 14, possibly because the animals had acclimatized to environmental heat stress.

Metabolic characteristics and oxidative damage to skeletal muscle in broiler chickens exposed to chronic heat stress.

Emerging evidence has shown that acute heat exposure affects metabolic characteristics and causes oxidative damage to skeletal muscle in birds. Little is known, however, about such phenomena under chronic heat stress conditions. To address this, we designed the present study to determine the influence of cyclic (32 to 24 to 32 degrees C: 32 degrees C for 8 h/d, 32-24-32HS ), and constant (32 and 34 degrees C, 32HS and 34HS, respectively) heat exposure on the metabolic and peroxide status in skeletal muscle of 4-wk-old male broiler chickens. Heat stress, particularly in the 32HS and 34HS groups, depressed feed intake and growth, while cyclic high temperature gave rise to a less severe stress response in performance terms. Malondialdehyde (MDA) levels in skeletal muscle were enhanced (P<0.05) by constant heat treatment; the degree of enhancement was not as large as the changes observed in our previous 'acute' heat stress model. The 3HADH (3-hydroxyacyl CoA dehydrogenase related to fatty acid oxidation) and CS (citrate synthase) enzyme activities were lowered (P<0.05) by both the cyclic and constant 34HS treatments, and constant 34HS group, respectively. These results suggest that chronic heat exposure decreases metabolic oxidation capacity in skeletal muscle of broiler chickens. On exposure to chronic heat stress, GPx activity remained relatively constant, though a temperature-dependent elevation in Cu/Zn-SOD activity was observed, implying that anti-oxidation ability was disturbed by the chronic stress condition. From these results it can be concluded that chronic heat stress did not induce oxidative damage to a major extent. This may probably be due to a decrease in metabolic oxidation capacity or due to a self-propagating scavenging system, though the system was not fully activated.

Impact of drying on dissolution behavior of carvedilol-loaded sustained release solid dispersion: development and characterization.

PURPOSE: The present study aimed to develop carvedilol (CAR)-loaded (25% w/w) sustained release solid dispersion (SRSD), for enhanced dissolution and to explore the applicability of different industrially accessible drying techniques. METHODS: SRSD-CAR containing different ratios of polymers were prepared and physicochemically characterized. Dissolution study was carried out in both sink and supersaturated conditions to identify the possible enhancement in dissolution behavior. RESULTS: Based on the solubility study, Kolliphor® P188 and Eudragit® RSPO (50:25, % w/w) ratio exhibited the highest solubility among the samples and was chosen as the optimal composition of SRSD-CAR for further characterization. The crystallinity assessments of the optimized formulation indicated amorphization of CAR in the formulation, bring about improved solubility of CAR. The infrared spectroscopic study revealed minor transitions; demonstrating the absence of significant interactions between drug and carrier. Furthermore, the SRSD-CAR exhibited immediate formation of nano particles when dispersed in water. Dissolution study revealed significant improvement in dissolution behavior, with a release of CAR in a gradual manner compared to crystalline CAR. From the dissolution kinetics analysis, the Korsmeyer Peppas model fit the best and diffusion was predominant in release of CAR. The drug release pattern showed insignificant differences between the SRSD-CAR formulations prepared by rotary vacuum drying and freeze drying. CONCLUSION: From these experimental findings, SRSD approach might be a favorable dosage option for CAR, offering improved biopharmaceutical properties.

Fog collecting biomimetic surfaces: Influence of microstructure and wettability.

We analyzed the fog collection efficiency of three different sets of samples: replica (with and without microstructures), copper wire (smooth and microgrooved) and polyolefin mesh (hydrophilic, superhydrophilic and hydrophobic). The collection efficiency of the samples was compared in each set separately to investigate the influence of microstructures and/or the wettability of the surfaces on fog collection. Based on the controlled experimental conditions chosen here large differences in the efficiency were found. We found that microstructured plant replica samples collected 2-3 times higher amounts of water than that of unstructured (smooth) samples. Copper wire samples showed similar results. Moreover, microgrooved wires had a faster dripping of water droplets than that of smooth wires. The superhydrophilic mesh tested here was proved more efficient than any other mesh samples with different wettability. The amount of collected fog by superhydrophilic mesh was about 5 times higher than that of hydrophilic (untreated) mesh and was about 2 times higher than that of hydrophobic mesh.

Genotypes and phenotypes of CYP3A in Bangladeshi population.

BACKGROUND: To investigate whether interindividual variation in CYP3A levels can partly be explained by genetic polymorphisms, this study was designed to phenotype 200 healthy Bangladeshi subjects by measuring urinary ratio of 6ß-hydroxy-cortisol/cortisol and to genotype all the subjects for the presence of CYP3A4*1B, *2, *4, *5, *6, *10 and *18 and CYP3A5*3 alleles. METHODS: For phenotyping, cortisol and 6ß-hydroxy-cortisol were extracted and quantified by HPLC from morning spot urine samples (n=200). Genotyping was done using the extracted genomic DNA from all the subjects followed by amplification of target alleles by PCR. Amplified DNA was digested by restriction enzymes (MboII, XcmI, BsmAI, ClaI, HinfI, HpyCH4III, HpaII and RsaI) followed by gel electrophoresis and sequencing to identify the targeted alleles. RESULTS: The ratio of 6ß-hydroxy-cortisol/cortisol ranged from 0.01 to 31.98 with an average of 3.91. No sample (n=200) was positive for CYP3A4*2, *4, *5, *6, *10 and *18 alleles. Two samples heterozygous for CYP3A4*1B (1.0%) and twenty six samples with the genotype CYP3A5*1/*1 (13.0%) were found to have relatively high 6ß-hydroxy-cortisol/cortisol ratios. CONCLUSION: CYP3A4 variant alleles are present at a low frequency in the Bangladeshi population whereas 50% of the Bangladeshi population carrying a CYP3A5*3/*3 genotype appear to show lower 6ß-hydroxy-cortisol/cortisol ratios compared with those with a CYP3A5*1/*1 genotype.