Preliminary Evaluation of 3D Printed Chitosan/Pectin Constructs for Biomedical Applications.

In the present study, chitosan (CS) and pectin (PEC) were utilized for the preparation of 3D printable inks through pneumatic extrusion for biomedical applications. CS is a polysaccharide with beneficial properties; however, its printing behavior is not satisfying, rendering the addition of a thickening agent necessary, i.e., PEC. The influence of PEC in the prepared inks was assessed through rheological measurements, altering the viscosity of the inks to be suitable for 3D printing. 3D printing conditions were optimized and the effect of different drying procedures, along with the presence or absence of a gelating agent on the CS-PEC printed scaffolds were assessed. The mean pore size along with the average filament diameter were measured through SEM micrographs. Interactions among the characteristic groups of the two polymers were evident through FTIR spectra. Swelling and hydrolysis measurements confirmed the influence of gelation and drying procedure on the subsequent behavior of the scaffolds. Ascribed to the beneficial pore size and swelling behavior, fibroblasts were able to survive upon exposure to the ungelated scaffolds.

The role of alkali in sweet potato starch-Mesona chinensis Benth polysaccharide gels: Gelation, rheological and structural properties.

According to the Chinese traditional black jelly production process, a critical step to ensure the quality of jelly is to add alkali to it. In this study, the effects of sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3) on the pasting, rheological, textural, and structural properties of sweet potato starch (SPS)-Mesona chinensis Benth polysaccharide (MCP) gels were evaluated. Adding Na2CO3 at low concentration reduced the final viscosity (FV) of SPS-MCP gels, whereas adding it at a high concentration increased the FV. Adding NaHCO3 can increase the FV of SPS-MCP gels in a concentration-dependent manner. Rheological results indicated that adding NaHCO3 at a low concentration decreased the storage modulus of SPS-MCP gels, whereas adding it at a high concentration increased the storage modulus. The storage modulus of SPS-MCP gels increased with increasing concentration of NaHCO3. The addition of Na2CO3 and NaHCO3 improved the textural properties of SPS-MCP gels and decreased the water mobility. Infrared results indicated that adding alkali can enhance the hydrogen bonding between SPS and MCP. Scanning electron microscopy results suggested that alkali can reduce the size of gels, and make the structure more compact.

Rheological properties of a neutral polysaccharide extracted from maca (Lepidium meyenii Walp.) roots with prebiotic and anti-inflammatory activities.

The rheological, prebiotic, and anti-inflammatory properties of neutral polysaccharide extracted from maca roots (MP) were investigated. MP was composed of arabinose, galactose, rhamnose, and glucose. In steady shear rheological properties, an increasing concentration of MP solution exhibited higher apparent viscosity (ηa,100) and consistency index (K) under acidic condition (pH 4). In dynamic rheological properties, the dynamic moduli (G' and G″) in the frequency sweep test from the MP solution were increased with increasing concentration and decreasing pH. The changes in dynamic moduli of the MP solution with various concentrations and pH values were stable during 1 h storage at 4 °C due to the enhancement of hydrogen bonding. According to the results of the temperature sweep test, an increasing concentration of MP solution increased dynamic moduli under acidic conditions. The prebiotic properties of MP induced a higher growth of Bifidobacterium longum ATCC15707 and Lactobacillus rhamnosus ATCC 7469 than inulin and increased acetic acid, propionic acid, and butyric acid more than inulin in vitro. Furthermore, MP inhibited lipopolysaccharide-induced NO production in RAW 264.7 cells, which indicated that an increasing concentration of MP enhanced anti-inflammatory activities. Therefore, MP is a potential functional material for the food and pharmaceutical industries.

Preparation of microemulsion containing Lycopersicon esculentum extract: In vitro characterization and stability studies.

Lycopene, the active component of Lycopersicon esculentum species, has been reported for the protecting capabilities against ultra-violet induced skin pigmentation, antioxygen and antityrosinase activities. In the present study, extract of tomato fruit was obtained from the Lycopersicon esculentum plant using solvent system comprised of hexaneethanol-acetone. The phyto chemical active constituent lycopene was then identified by spectrophotometric technique at 470nm. Micro emulsions were developed containing different ratio of water, isopropyl myristate (oil), tween 80 and propylene glycol as surfactant and co-surfactant respectively via pseudoternary phase diagram. Various physicochemical tests were performed including globular size, conductivity, viscosity, scanning electron microscopy (SEM), refractive index (RI) and pH measurement for the formulation characterization. Results of physical and chemical stability studies showed that the micro emulsion with proportion of surfactant: co-surfactant of 2:1 (Smix) was found to be optimized formulation and with enhanced stability. Therefore, concluded that the stability of the micro emulsion was dependent on the proportions of surfactant co-surfactant, water and oil in the preparation.

Development, characterization and evaluation of ginger extract loaded microemulsion: In vitro and Ex vivo release studies.

Zingeber officinale (ginger) has been used for a long time in conventional medicine for the management of many diseases most important of which is inflammatory diseases. The aim of this study was formulation of topical microemulsion system to enhance the solubility, stability and release profile of ginger extract, as it is unstable in the presence of light, air, heat and long term storage. The solubility of ginger extract in different oils, surfactants, and cosurfactants was determined in order to find the optimal components for microemulsion. Isopropyl myristate (IPM) was selected as oil phase, tween 80 and PEG 400 were selected as surfactant and co-surfactant respectively based on highest solubility values. Pseudo-ternary phase diagram was constructed in order to find out the microemulsion region. The prepared microemulsions were evaluated for pH, viscosity, conductivity, refractive index, globular size, zeta potential, polydispersity index, ginger extract content, in-vitro and ex-vivo release profiles. The formulation GE1 showed best physicochemical properties with smallest globular size (19.75nm), highest release rate and flux value. It also showed significant (p<0.05) anti-inflammatory effect as compared to reference piroxicam drug solution. It is concluded that ginger extract can be used to develop stable microemulsion system with better skin permeation and promising antiinflammatory activity.

Holistic QbD approach for hot-melt extrusion process design space evaluation: Linking materials science, experimentation and process modeling.

The aim of this work was to investigate the relationship between formulation material properties, process parameters and process performance for the manufacturing of amorphous solid dispersions via hot-melt extrusion (HME) using experimentation coupled with process modeling. Specifically, we evaluated the impact of the matrix copovidone melt rheology with and without the addition of a plasticizing surfactant, polysorbate 80, while also varying the process parameters, barrel temperature and screw speed, and keeping fill volume constant. To correlate the process performance to a critical quality attribute, we used telmisartan as an indicator substance by processing at temperatures below its solubility temperature in the polymeric matrix. We observed a broader design space of HME processes for the plasticized formulation with respect to screw speed than for the copovidone-only matrix formulation. This observation was determined by the range of observed melt temperatures in the extruder, both measured and simulated. The reason was not primarily linked to a reduced shear-thinning behavior, characterized by the power law index, n, but instead more to an overall reduced melt viscosity during extrusion and zero-shear rate viscosity, η0, accordingly. We also found that the amount of residual crystallinity of telmisartan correlated with the simulated maximum melt temperature in the extruder barrel. This finding confirmed the applicability of the temperature-dependent API-matrix solubility phase diagram for HME to process development. Given the complex inter-dependent relationships between material properties, process and performance, process modeling combined with reduced laboratory experimentation was established as a holistic approach for the evaluation of Quality-by-Design-based HME process design spaces.

Topical application and oral supplementation of peptides in the improvement of skin viscoelasticity and density.

BACKGROUND: The combination of oral supplementation and topical formulations to the improvement of skin conditions has been proposed as an innovative approach to obtain effective treatments. However, studies comparing the effectiveness of each type of treatments are still in lack. This way, the objective of this work was to evaluate the clinical efficacy of a dermocosmetic formulation with di- and tripeptides, as well the effects of an oral supplementation based on hydrolyzed collagen through biophysical and skin imaging techniques. METHODS: Sixty healthy female subjects, aged between 40 and 50 years, were enrolled, being separated in 3 groups: topical formulation, oral supplementation, and oral placebo. The stratum corneum water content, skin viscoelasticity, dermis echogenicity, and skin pores parameters were evaluated. RESULTS: The group with the topical formulation showed a significant increase in the stratum corneum water content and skin elasticity after 28-day period and also acted in the dermis echogenicity after 90 days with the formulation with peptides. The oral supplementation acted on skin elasticity and presented a more pronounced effect on dermis echogenicity, reducing skin pores after 90-day period. CONCLUSION: The obtained results with oral supplementation and topical application of hydrolyzed proteins were considered complementary in the improvement of general skin conditions, acting in different mechanisms.

A high-throughput QCM chip configuration for the study of living cells and cell-drug interactions.

In this study, we present a novel design of interference-free, negligible installation-induced stress, suitable for the fabrication of high-throughput quartz crystal microbalance (HQCM) chips. This novel HQCM chip configuration was fabricated using eight independent yet same-batch quartz crystal resonators within a common glass substrate with eight through-holes of diameter slightly larger than that of the quartz resonator. Each quartz resonator's rim was adhered to the inner part of the through-hole via silicone glue to form the rigid (quartz)-soft (silicone)-rigid (glass) structure (RSRS) which effectively eliminates the acoustic couplings among different resonators and largely alleviates the installation-induced stresses. The consistence of the eight resonators was verified by very similar equivalent circuit parameters and very close response slopes to liquid density and viscosity. The HQCM chip was then employed for real-time and continuous monitoring of H9C2 cardiomyoblast adhesions and viscoelastic changes induced by the treatments of two types of drugs: drugs that affect the cytoskeletons, including nocodazole, paclitaxel, and Y-27632, and drugs that affect the contractile properties of the cells: verapamil and different dosages of isoprenaline. Meanwhile, we compared the cytoskeleton affecting drug-induced viscoelastic changes of H9C2 with those of human umbilical vein endothelial cells (HUVECs). The results described here provide the first solution to fabricate HQCM chips that are free from the limitation of resonator number, installation-induced stress, and acoustic interferences among resonators, which should find wide applications in areas of cell phenotype assay, cytotoxicity test, drug evaluation and screening, etc. Graphical abstract Schematic illustration of the principle and configuration of interference-free high-throughput QCM chip to evaluate and screen drugs based on cell viscoelasticity.

Nutraceutical, Anti-Inflammatory, and Immune Modulatory Effects of ß-Glucan Isolated from Yeast.

ß-Glucan is a dietary fibre, found in many natural sources, and controls chronic metabolic diseases effectively. However, ß-glucan from the yeast has rarely been investigated. Objectively, conditions were optimized to isolate ß-glucan from the yeast (max. 66% yield); those optimized conditions included 1.0 M NaOH, pH 7.0, and 90°C. The purity and identity of the isolated ß-glucan were characterized through FT-IR, SEM, DSC, and physicofunctional properties. The obtained results from DSC revealed highly stable ß-glucan (m.p., 125°C) with antioxidant activity (TAC value 0.240 ± 0.0021 µg/mg, H2O2 scavenging 38%), which has promising bile acid binding 40.463% and glucose control (in vitro). In line with these results, we evaluated the in vivo anti-inflammatory potential, that is, myeloperoxidase activity and reduction in MDA and NO; protective effect on proteins and keeping viscosity within normal range exhibited improvement. Also, the in vivo cholesterol binding and reduction in the skin thickness by ß-glucan were highly encouraging. Finally, our results confirmed that yeast ß-glucan is effective against some of the inflammatory and oxidative stress markers studied in this investigation. In general, the effect of 4% ß-glucan was more noticeable versus 2% ß-glucan. Therefore, our results support the utilization of ß-glucan as a novel, economically cheap, and functional food ingredient.

Glucose triggered enhanced solubilisation, release and cytotoxicity of poorly water soluble anti-cancer drugs fromT1307 micelles.

Tetronic® 1307 (here after written as T1307) is a hydrophilic ethylene oxide-propylene oxide (EO-PO) star block copolymer with long EO chains (Total MW- 18000 and 70% EO). Although biocompatible, its use as a nanocarrier is restricted owing to its high critical micelle concentration (CMC) and temperature (CMT). We examined if the addition of glucose, a common pharmaceutical ingredient promotes micellization. Scattering and thermal studies show formation of stable unimodal micelles and cloud point (CP) decreased linearly. The solubilization of anticancer drugs viz. curcumin (CN) and quercetin (QN) demonstrates improved controlled release kinetics and cytotoxicity. On the whole, modulation in micellar behaviour by glucose opens enchanting possibility of using T1307 micelles as nanoreservoirs.

Myosin MgADP Release Rate Decreases as Sarcomere Length Increases in Skinned Rat Soleus Muscle Fibers.

Actin-myosin cross-bridges use chemical energy from MgATP hydrolysis to generate force and shortening in striated muscle. Previous studies show that increases in sarcomere length can reduce thick-to-thin filament spacing in skinned muscle fibers, thereby increasing force production at longer sarcomere lengths. However, it is unclear how changes in sarcomere length and lattice spacing affect cross-bridge kinetics at fundamental steps of the cross-bridge cycle, such as the MgADP release rate. We hypothesize that decreased lattice spacing, achieved through increased sarcomere length or osmotic compression of the fiber via dextran T-500, could slow MgADP release rate and increase cross-bridge attachment duration. To test this, we measured cross-bridge cycling and MgADP release rates in skinned soleus fibers using stochastic length-perturbation analysis at 2.5 and 2.0 µm sarcomere lengths as pCa and [MgATP] varied. In the absence of dextran, the force-pCa relationship showed greater Ca2+ sensitivity for 2.5 vs. 2.0 µm sarcomere length fibers (pCa50 = 5.68 ± 0.01 vs. 5.60 ± 0.01). When fibers were compressed with 4% dextran, the length-dependent increase in Ca2+ sensitivity of force was attenuated, though the Ca2+ sensitivity of the force-pCa relationship at both sarcomere lengths was greater with osmotic compression via 4% dextran compared to no osmotic compression. Without dextran, the cross-bridge detachment rate slowed by ∼15% as sarcomere length increased, due to a slower MgADP release rate (11.2 ± 0.5 vs. 13.5 ± 0.7 s-1). In the presence of dextran, cross-bridge detachment was ∼20% slower at 2.5 vs. 2.0 µm sarcomere length due to a slower MgADP release rate (10.1 ± 0.6 vs. 12.9 ± 0.5 s-1). However, osmotic compression of fibers at either 2.5 or 2.0 µm sarcomere length produced only slight (and statistically insignificant) slowing in the rate of MgADP release. These data suggest that skeletal muscle exhibits sarcomere-length-dependent changes in cross-bridge kinetics and MgADP release that are separate from, or complementary to, changes in lattice spacing.

[Salivation in children during anticancer chemotherapy].

The study aimed to assess the needs and options for salivation management in children treated with antileukemic chemotherapy. In a preliminary cross-sectional study the saliva flow rate and viscosity were evaluated in 75 leukemic children that received chemotherapy with methotrexate in low dose (44 people, 44 episode, group 1), or in high-dose (31 people, 42 episode, group 2), and in 25 healthy children (group 3). Then, 26 children were randomly divided into two groups in the 70 episodes course of high-dosed chemotherapy, and received acetylcysteine (A) or only standard oral management (S) for 1-10 day of treatment. Parameters of salivation and children performance (Lansky et al.) were evaluated. Mann-Whitney U-test was used for analysis. In group 1, 2 and 3 the flow rate (Me [LQ/HQ]) was 0.5 [0.3; 0.8]; 0.9 [0.6; 1.2] and 0.5 [0.3; 0.6] ml/min respectively (p1-3>0.05; p<0.01; p1-2<0.05). Viscosity levels in group 1, 2 and 3 were 2.75 [3.67; 3.67], 10.05 [5.3; 26.0] and 3.9 [2.7; 6.5] unites respectively (p1-3>0.05; p2, 3<0.01; p1, 2<0.01). In group A and S the flow rate was 2.7 [0.5; 4.1] and 0.4 [0.1; 2.2] ml/min (р<0.05); viscosity was 1.5 [1.2; 4.1] and 6.4 [5.3; 8.1] unites (р<0.001), performance Lansky index was 80 [65; 90] and 70 [60; 80] (р<0.01) respectively. Salivation dysfunction complicates the chemotherapy with high-dosed methotrexate in children: it is indicated by high viscosity combined with elevated flow rate. Acetylcysteine normalizes saliva viscosity and improves children's performance.

Effect of α-Amylase, Papain, and Spermfluid treatments on viscosity and semen parameters of dromedary camel ejaculates.

Ejaculates from five clinically healthy dromedary camels (Camelus dromedarius) were used to evaluate the effects of different enzymatic treatments (Amylase, Papain, Spermfluid) on liquefaction and seminal parameters. After collection, ejaculates were divided into 5 aliquots: (1) kept undiluted (control); or diluted 1:1 with: (2) Tris-Citrate-Fructose (TCF), (3) TCF containing Amylase, (4) TCF containing Papain or (5) Spermfluid containing Bromelain. At 120 min after dilution, each aliquot was evaluated, at 20-min intervals, for viscosity, motility, viability and agglutination. Only the aliquots diluted with TCF containing Papain underwent complete liquefaction. Sperm motility decreased significantly during the observation times, except for the samples diluted with Spermfluid (P=0.005). Diluted samples showed different levels of agglutination, with the lowest being observed in the control and the highest in the Papain-treated samples. The viscosity of dromedary camel ejaculates could be effectively reduced by using the proteolytic enzyme Papain.

Evaluation of a Bacillus direct-fed microbial candidate on digesta viscosity, bacterial translocation, microbiota composition and bone mineralisation in broiler chickens fed on a rye-based diet.

1. The effects of the dietary inclusion of a Bacillus-based direct-fed microbial (DFM) candidate on digesta viscosity, bacterial translocation, microbiota composition and bone mineralisation were evaluated in broilers consuming rye-based diets. 2. In the present study, control mash rye-based diets (CON) or Bacillus-DFM supplemented diets (TRT) were administered ad libitum to male broilers in three independent experiments. 3. In Experiments 1 and 2 (n = 25/group), liver samples were taken to evaluate bacterial translocation, digesta samples were used for viscosity measurements and the intestinal microbial flora was evaluated from different intestinal sections to enumerate total recovered gram-negative bacteria (TGB), lactic acid bacteria (LAB) and anaerobic bacteria (TAB). Additionally, both tibias were removed for assessment of bone quality. 4. In Experiment 3, each experimental group had 8 replicates of 20 chickens (n = 160/group). Weekly, body weight (BW), feed intake (FI) and feed conversion ratio (FCR) were evaluated. At d 28-of-age, samples were taken to determine bacterial translocation, digesta viscosity and bone quality characteristics. 5. In all experiments, consumption of Bacillus-DFM reduced bacterial translocation to the liver and digesta viscosity. Additionally, DFM supplementation improved BW, bone quality measurements and FCR. Moreover, chickens fed on the Bacillus-DFM diet in Experiments 1 and 2 showed a significant reduction in the number of gram-negative and anaerobic bacteria in the duodenal content compared to control. 6. In summary, chickens fed on a rye-based diet without DFM inclusion showed an increase in bacterial translocation and digesta viscosity, accompanied by reduced performance and bone quality variables relative to the Bacillus-DFM candidate group. Hence, incorporation into the feed of a selected DFM ameliorated the adverse anti-nutritional effects related to utilisation of rye-based diets in broilers chickens.

Physicochemical properties and biological activities of Thai plant mucilages for artificial saliva preparation.

CONTEXT: Plant mucilages can be found in various parts of several Thai plants, which can be used as thickening, moisturizing, and lubricating agents in artificial saliva formulations. OBJECTIVE: The objective of this study was to evaluate the physicochemical properties, biological activity, and cytotoxicity of Thai plant mucilages. MATERIALS AND METHODS: The mucilages from Thai plants were extracted by various processes (temperature and pH variation, microwave oven, steam, and Tris-HCl buffer extraction). The viscosity and the rheology were evaluated using viscometer. Antioxidative activities including DPPH radical scavenging and metal chelating activities were investigated. The mucilages were determined for cytotoxicity on normal human gingival fibroblasts and anti-adherent activity of Streptococcus mutans. RESULTS: Mucilages from Ocimum citriodorum Vis. (Lamiaceae), Artocarpus heterophyllus Lam. (Moraceae), Abelmoschus esculentus (Linn.) Moench. (Malvaceae), and Basella alba Linn. (Basellaceae) exhibited pseudoplastic non-Newtonian rheology. The highest DPPH radical-scavenging and metal-chelating activities were observed in the mucilages from B. alba (microwave, 3 min) and A. esculentus (microwave, 1 min) with the SC50 and MC50 values (50% of scavenging activity and 50% of metal chelating activity, respectively) of 0.71 ± 0.32 and 1.11 ± 0.52 mg/ml, respectively. Most mucilages exhibited no cytotoxicity to normal human gingival fibroblasts. The mucilage from A. esculentus (microwave, 5 min) gave the shortest wetting time of 2.75 ± 0.51 min. The highest S. mutans adhesion inhibition was observed in A. esculentus (pH 11) of 5.39 ± 9.70%. DISCUSSION AND CONCLUSION: This study has indicated the suitable physicochemical and biological properties and the potential application of mucilages from Thai plants for artificial saliva preparation.

Influence of sulphate on the composition and antibacterial and antiviral properties of the exopolysaccharide from Porphyridium cruentum.

AIMS: The influence of two culture media and three different concentrations of sulphate in the medium on the growth of two strains of Porphyridium cruentum and on the production, composition and viscoelastic characteristics, and antimicrobial properties of the sulphated exopolysaccharide (EPS) were studied. MAIN METHODS: A Bohlin C50 rheometer was used to evaluate the viscosity and elasticity of the EPS solutions. HSV virus, types 1 and 2, Vaccinia virus and Vesicular stomatitis virus were used along with two Gram-negative (Escherichia coli and Salmonella enteritidis) and one Gram-positive (Staphylococcus aureus) bacteria, for testing the antimicrobial activity of EPS. KEY-FINDINGS: The growth of microalgae was higher in NTIP medium and the production of EPS was enhanced by sulphate 21mM. The protein content of the EPS was enhanced by the addition of sulphate 52mM and 104mM; this concentration also induced an increase in sulphate content of the EPS. However, neither the contents of EPS in carbohydrates and uronic acids were affected by the culture medium supplementation in sulphate. In general, the EPS from the Spanish strain presented a higher antiviral activity than the EPS from the Israeli strain. All EPS extracts revealed a strong activity against V. stomatitis virus, higher than the activity of all chemical compounds tested. The EPS from the Israeli strain also presented antibacterial activity against S. enteritidis. SIGNIFICANCE: Enrichment of the culture medium with sulphate improved protein and sulphate content of EPS. EPS extracts presented a relevant activity against V. stomatitis virus and S. enteritidis bacterium.

Integration of a kraft pulping mill into a forest biorefinery: pre-extraction of hemicellulose by steam explosion versus steam treatment.

Growing interest in alternative and renewable energy sources has brought increasing attention to the integration of a pulp mill into a forest biorefinery, where other products could be produced in addition to pulp. To achieve this goal, hemicelluloses were extracted, either by steam explosion or by steam treatment, from Eucalyptus globulus wood prior to pulping. The effects of both pre-treatments in the subsequent kraft pulping and paper strength were evaluated. Results showed a similar degree of hemicelluloses extraction with both options (32-67% of pentosans), which increased with the severity of the conditions applied. Although both pre-treatments increased delignification during pulping, steam explosion was significantly better: 12.9 kappa number vs 22.6 for similar steam unexploded pulps and 40.7 for control pulp. Finally, similar reductions in paper strength were found regardless of the type of treatment and conditions assayed, which is attributed to the increase of curled and kinked fibers.

Controlled production of exopolysaccharides from Enterobacter A47 as a function of carbon source with demonstration of their film and emulsifying abilities.

The bacterium Enterobacter A47 has demonstrated the ability to synthesise distinct exopolysaccharides (EPS) as a function of the substrate used. The culture's performance was evaluated in experiments using either glucose or xylose, as single carbon sources, and compared with the substrate (glycerol) used in previous studies. The highest EPS production (13.23 g L(-1)) was obtained in the glucose fed assay, with a volumetric productivity of 3.38 g L(-1) day(-1). The use of xylose resulted in lower productivity (1.39 g L(-1) day(-1)). The synthesised polymers have the same main sugar monomers (fucose, glucose, galactose and glucuronic acid), but their relative proportion varied with the substrate used. The acyl groups' content and composition were also affected by the substrate used. The polymers produced from glycerol (EPS-s) and glucose (EPS-g) had identical shear-thinning behaviour and good emulsion-stabilising capacity and their films had similar mechanical and water vapour properties. However, the emulsions stabilised with EPS-g were less stable and destabilised within short periods of time or when subjected to heat and freezing/thawing procedures. On the other hand, the polymer produced from xylose had little emulsion-stabilising capacity and lower apparent viscosity than EPS-s and EPS-g, but its films were considerably more elastic.

Studies on the anti-asthmatic and antitussive properties of aqueous leaf extract of Bryophyllum pinnatum in rodent species.

OBJECTIVE: To evaluate the antiasthmatic and antitussive properties of the aqueous leaf extract of Bryophyllum pinnatum (B. pinnatum) (BP) Lam. METHODS: Ovalbumin-sensitized guinea pigs which were treated with BP for 21 consecutive days were exposed to 0.2% histamine aerosol in a glass chamber. Mucus viscosity, white blood cell and lymphocyte counts and tracheal wall morphometry were measured. Bouts of cough were counted pre and post acute exposure of extract-treated (× 7 d) guinea pigs to 7.5% citric acid aerosol in a chamber. Phenol red expectoration was estimated in mice after 7 d of daily administration of BP. RESULTS: Doses of 200 and 400 mg/kg/day (×21 d) BP significantly increased the time for guinea pigs to experience preconvulsive dyspnoea. BP and salbutamol (0.5 mg/kg/day ×21 d) reduced mucus viscosity in the sensitized group to values comparable with controls. White blood cell, lymphocyte counts and tracheal morphometry were not significantly altered. Both doses of BP also significantly reduced the bouts of cough but only 400 mg/kg/day significantly inhibited the amount of phenol red secreted. CONCLUSIONS: BP has demonstrated antiasthmatic and antitussive properties in these rodent models. These properties may underscore its use in Nigerian ethnomedicine.

The effect of glycosaminoglycan enzymes and proteases on the viscosity of alpaca seminal plasma and sperm function.

In order to advance the development of cryopreservation and other assisted reproductive technologies in camelids it is necessary to eliminate the viscous component of the seminal plasma without impairing sperm function. It has been postulated that glycosaminoglycans (GAGs) or proteoglycans are responsible for this viscosity. This study investigated the effect of the GAG enzymes hyaluronidase, chondroitinase ABC and keratanase and the proteases papain and proteinase K on seminal plasma viscosity and sperm function in order to aid identification of the cause of seminal plasma viscosity and propose methods for the reduction of viscosity. Sperm motility, DNA integrity, acrosome integrity and viability were assessed during 2h incubation. All enzymes reduced seminal plasma viscosity compared to control (P<0.001) although papain was most effective, completely eliminating viscosity within 30 min of treatment. Sperm motility and DNA integrity was not affected by enzyme treatment. The proportion of viable, acrosome intact sperm was reduced in all enzyme treated samples except those treated with papain (P<0.001). These findings suggest that proteins, not GAGs are the main cause of alpaca seminal plasma viscosity. Papain treatment of alpaca semen may be a suitable technique for reduction of seminal plasma viscosity prior to sperm cryopreservation.