Symbiotic bacteria direct expression of an intestinal bactericidal lectin

The mammalian intestine harbors complex societies of beneficial bacteria that are maintained in the lumen with minimal penetration of mucosal surfaces. Microbial colonization of germ-free mice triggers epithelial expression of RegIIIgamma, a secreted C-type lectin. RegIIIgamma binds intestinal bacteria but lacks the complement recruitment domains present in other microbe-binding mammalian C-type lectins. We show that RegIIIgamma and its human counterpart, HIP/PAP, are directly antimicrobial proteins that bind their bacterial targets via interactions with peptidoglycan carbohydrate. We propose that these proteins represent an evolutionarily primitive form of lectin-mediated innate immunity, and that they reveal intestinal strategies for maintaining symbiotic host-microbial relationships.     

Sulfated Polysaccharide Extracted from the Green Algae Codium bernabei: Physicochemical Characterization and Antioxidant,Anticoagulant and Antitumor Activity

Codium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 °C) and showed antioxidant activity according to the ABTS^•+ and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 µg mL⁻¹ concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 µg mL⁻¹. Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource.     

Effects of Algae and Shell Pigment Extract‐supplemented Diets on Shell Pigmentation and Growth Performance of Pacific Abalone,Haliotis discus hannai

To improve shell pigmentation and growth performance of Pacific abalone, five extruded diets were prepared by supplementing a formulated control diet with 3% each of three species of algae (Pacific dulse, Porphyra yezoensis, Spirulina) and a pigment extract from the abalone shells (0.02%). Each of the five diets and a commercial feed were randomly assigned to three containers each stocked with 1000 juvenile Pacific abalone (2 g per individual) in a flow‐through seawater system for a 5‐mo feeding trial. Test results showed: (1) all the supplements significantly (P < 0.05) increased percentages of dark‐brown shelled abalone in the test treatments, relative to the control treatment; (2) the abalone fed the experimental diets achieved significantly (P < 0.05) greater final weight, shell‐length growth rates, and higher meat protein contents than those fed the commercial feed (P < 0.05); and (3) the abalone fed the Spirulina‐supplemented diet achieved the best overall growth, pigmentation performances, and feed conversion ratio; and the Pacific dulse supplement generated the highest protein content in abalone meat product (P < 0.05) among the tested diets. These results demonstrate the potential of locally made feed, which can generate desirable characteristics in abalone under aquaculture conditions.     

Energy Balance of Callinectes rathbunae Contreras 1930 in Floating Cages in a Tropical Coastal Lagoon

The genus Callinecres is ecologically important in the coastal lagoon region of the Gulf of Mexico. This study was conducted to test the feasibility of raising these crabs in a system of floating cages and to measure their scope for growth in a tropical coastal lagoon of the Gulf of Mexico. The equation P = As - (R + E + N) was used to estimate the scope for growth (P) for C. rathbunae under experimental conditions for 21 days. Ingested food was 3% of body weight. Assimilation (As) was 73% of assimilated energy, 21.4% was channeled to respiration (R), 2% to excretion (N) and 0.16% to exuvia (E). The remainder of the energy was channeled to growth at a net efficiency of 76%. Significant differences were not found between the calculated scope for growth and the growth achieved in the culture system ( P > 0.05). These results support the energy balance equation and suggest that the cultivation of C. rathbunae in floating cages is possible.     

Validation of thromboelastometry in horses

Background: Thromboelastometry is used for identifying or monitoring coagulation abnormalities. It has been validated in several species but not in horses and the characteristics of the equine thromboelastogram have not yet been detailed. Objectives: The purpose of this study was to validate a thromboelastometer to be used with equine blood and to define the normal equine thromboelastogram. Methods: A Rotem-gamma thromboelastometer (Pentapharm GmbH, Munich, Germany) was used on 38 citrated blood samples to investigate native coagulation, the intrinsic and extrinsic pathways, the function of fibrinogen (largely dependent on its concentration), and the presence of fibrinolysis. Using classic validation approaches, we evaluated the imprecision of the method and the influence of hemolysis and storage time and temperature. The normal thromboelastogram was defined in both saddle and racing horses (the latter sampled before and after the race). Results: For imprecision tests, the analytical variations were <10%. The equine thromboelastogram had a pattern similar to those of other species, but the intrinsic and extrinsic pathways were less and more efficient, respectively. Reference intervals in racing horses, especially after exercise, were different from those of saddle horses, most likely due to a higher RBC mass. Coagulability decreased in hemolyzed samples and significant changes were found between nonrefrigerated and refrigerated blood samples stored for 20 hours. Conclusions: The Rotem-gamma thromboelastometer is a precise instrument for use with equine blood samples. The equine thromboelastogram is similar to that of other species, but reference intervals vary with aptitude and exercise. Hemolysis and refrigeration alter thromboelastometric results.     

Effect of different penetrating and non‐penetrating cryoprotectants and media temperature on the cryosurvival of vitrified in vitro produced porcine blastocysts

The aim of this study was to determine the most efficient vitrification protocol for the cryopreservation of day 7 in vitro produced (IVP) porcine blastocysts. The post‐warm survival rate of blastocysts vitrified in control (17% dimethyl sulfoxide + 17% ethylene glycol [EG] + 0.4 mol/L sucrose) and commercial media did not differ, nor did the post‐warm survival rate of blastocysts vitrified in medium containing 1,2‐propandiol in place of EG. However, vitrifying embryos in EG alone decreased the cryosurvival rate (55.6% and 33.6%, respectively, p < .05). Furthermore, the post‐warm survival rates of blastocysts vitrified with either trehalose or sucrose as the non‐penetrating cryoprotectant did not differ. There was also no significant difference in post‐warm survival of blastocysts vitrified in control (38°C) media and room temperature (22°C) media with extended equilibration times, although when blastocysts were vitrified using control media at room temperature, the post‐warm survival rate increased (56.8%, 57.3%, 72.5%, respectively, p < .05). The findings show that most cryoprotectant combinations examined proved equally effective at supporting the post‐warm survival of IVP porcine blastocysts. The improved post‐warm survival rate of blastocysts vitrified using media held at room temperature suggests that the cryoprotectant toxicity exerted in 22°C media was reduced.     

Morphological indices for canine spermatozoa based on the World Health Organization laboratory manual for human semen

Attempting to contribute to the development of a more objective morphological evaluation of dog spermatozoa, in this study the indices of multiple sperm defects (multiple abnormalities index [MAI]; teratozoospermic index [TZI]; sperm deformity index [SDI]) were calculated following the World Health Organization (WHO) guidelines. In Experiment I, the concordance of MAI, TZI and SDI with the proportions of morphologically normal spermatozoa (MNS) was evaluated in fresh ejaculated spermatozoa (dogs = 47). In Experiment II, the potential role of indices as prognostic values was assessed in spermatozoa of different origin and treatment (fresh ejaculated: n = 6; fresh epididymal: n = 6; frozen‐thawed ejaculated: n = 6) by their correlation with different semen parameters (motility, membrane integrity and acrosome status) and with an in vitro sperm function test. Samples with different proportions of MNS showed different values of SDI, the index that better represented the decline of sperm morphology in both fresh and frozen‐thawed samples (Exp. I and II; p < 0.05). No correlations between indices and semen parameters were observed (Exp. II), but when samples were evaluated collectively, negative correlations (SDI‐motility, p = 0.01; SDI‐acrosome integrity, p = 0.002) were found. Including all the defects of each spermatozoon, SDI might be a useful index during morphological analysis and better discriminates the increase in multiple defects. A more objective morphological evaluation for dog spermatozoa was achieved by the WHO method, and in vitro tests allowed to elucidate the validity of SDI as prognostic indicator of in vitro fertilizing potential.