Enzyme-assisted extraction of moniliformin from extruded corn grits

Water has been known to be the ideal solvent for moniliformin but is not suitable to extract this toxin from cooked matrices due to instant swelling upon addition of the solvent. In this study, an improved method to extract moniliformin from extruded corn grits using alpha-amylase was developed. In an effort to optimize the method, the efficacy of using a protease was also studied. Treatment with alpha-amylase resulted in a clear solution with decreased suspended solid content as measured by transmittance (%T), which improved from 0 to 96% in 10 min. The detected level of moniliformin from extruded corn grits was increased to 4.02 mug/g when extracted with 1% tetrabutylammonium hydrogen sulfate following alpha-amylase treatment compared to 2.56 microg/g when it was extracted with 90% acetonitrile without enzyme treatment. The average recovery of moniliformin from extruded corn grits was 96% when alpha-amylase was used in the extraction procedure. Overall, the amounts of moniliformin detected in extruded corn grits increased significantly by using enzyme hydrolysis. Chromatographic separation was also benefited by lesser interference and improved peaks.     

Seasonal variations of bromophenols in brown algae (Padina arborescens,Sargassum siliquastrum,and Lobophora variegata) collected in Hong Kong

Distributions and seasonal variations of the key seafood flavor compounds including 2-bromophenol, 4-bromophenol, 2,4-dibromophenol, 2,6-dibromophenol, and 2,4,6-tribromophenol in three species of brown algae (Padina arborescens, Sargassum siliquastrum, and Lobophora variegata) found in Hong Kong waters were investigated. Bromophenols were extracted by simultaneous steam distillation and solvent extraction apparatus and analyzed by gas chromatography-mass spectrometry. On a dried weight basis, the total bromophenol content (TBC) determined varied widely with seasons (from 40.9 to 7030 ng/g). The TBCs detected were higher in winter and lower in summer. Except for 2-bromophenol, the rest of the bromophenols were detected in all of the algal samples. The TBC of L. variegata was generally the highest among all of the algae collected. Relatively high concentrations of bromophenols in algae supported the fact that marine algae were major producers of bromophenols in the marine environment.     

Isolation and characterization of phosphate solubilizing bacteria from the rhizosphere of crop plants of Korea

Whole-cell fatty acids methyl ester (FAME) profile and 16S rDNA sequence analysis were employed to isolate and identify the bacterial groups that actively solubilized phosphates in vitro from rhizosphere soil of various crops of Korea. Out of several hundred colonies that grew on Pikovskaya's medium 13 best isolates were selected based on the solubilization of insoluble phosphates in liquid culture and further characterized and identified. They were clustered under the genera Enterobacter, Pantoea and Klebsiella and the sequences of three representative strains were deposited in the GenBank nucleotide sequence data library under the accession numbers AY335552, AY335553, AY335554.     

In Vitro Performance Testing of Two Arcuate Oscillating Saw Blades Designed for Use During Tibial Plateau Leveling Osteotomy

Objective: To test the cutting performance of 2 commercially available oscillating saws designed for use during tibial plateau leveling osteotomy (TPLO) and to evaluate the influence of saline irrigation on cutting performance. Study Design: In vitro experimental study. Sample Population: Composite polyurethane test blocks (n=40); 24 mm TPLO saw blades. Methods: Controlled force cutting tests were performed using custom‐made laminated bone substitute blocks to model the canine proximal tibia. Half of the trials were irrigated with 0.9% saline solution. Outcome measures were test block temperature (measured 1.5 mm from the cutting zone), cutting rate, and cutting surface wear. Durability was measured by recording change in performance over multiple consecutive trials. Results: The Synthes blade cut the test blocks with ～64% less heat generation and at a 63% faster cutting rate compared with the Slocum blade. Although wear of the Synthes blade was ～50% greater after 19 uses, this did not negatively impact cutting performance. Saline irrigation produced no significant effect on peak cutting temperature but significantly reduced cutting rate for both saws. Conclusions: Our results favor the Synthes blade in terms of cutting performance and the Slocum blade in terms of wear resistance.     

Effect of trehalose coating on basic fibroblast growth factor release from tailor-made bone implants

Artificial bone implants are often incorporated with osteoinductive factors to facilitate early bone regeneration. Calcium phosphate, the main component in artificial bone implants, strongly binds these factors, and in a few cases, the incorporated proteins are not released from the implant under conditions of physiological pH, thereby leading to reduction in their osteoinductivity. In this study, we coated tailor-made bone implants with trehalose to facilitate the release of basic fibroblast growth factor (bFGF). In an in vitro study, mouse osteoblastic cells were separately cultured for 48 hr in a medium with a untreated implant (T-), trehalose-coated implant (T+), bFGF-incorporated implant (FT-), and bFGF-incorporated implant with trehalose coating (FT+). In the FT+ group, cell viability was significantly higher than that in the other groups (P<0.05). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that trehalose effectively covered the surface of the artificial bone implant without affecting the crystallinity or the mechanical strength of the artificial bone implant. These results suggest that coating artificial bone implants with trehalose could limit the binding of bFGF to calcium phosphate.     

Anti‐tumour activity of oncolytic reovirus against canine histiocytic sarcoma cells

Canine histiocytic sarcoma is an aggressive, fatal neoplastic disease with a poor prognosis. Lomustine is generally accepted as the first‐line systemic therapy, although this compound does not provide complete regression. Therefore, research into a novel approach against canine histiocytic sarcoma is needed. However, anti‐tumour effects of oncolytic therapy using reovirus against histiocytic sarcoma are unknown. Here, we showed that reovirus has oncolytic activity in canine histiocytic sarcoma cell lines in vitro and in vivo. We found that reovirus can replicate and induce caspase‐dependent apoptosis in canine histiocytic sarcoma cell lines. A single intra‐tumoural injection of reovirus completely suppressed the growth of subcutaneously grafted tumours in NOD/SCID mice. Additionally, we demonstrated that susceptibility to reovirus‐induced cell death was attributable to the extent of expression of type I interferons induced by reovirus infection in vitro. In conclusion, oncolytic reovirus appears to be an effective treatment option for histiocytic sarcoma, and therefore warrants further investigation in early clinical trials.     

Seroprevalence of spotted fever group rickettsiae in canines along the United States–Mexico border

Portions of northern Mexico are experiencing a re‐emergence of Rocky Mountain spotted fever (RMSF), a tickborne disease caused by Rickettsia rickettsii, a member of the spotted fever group of rickettsiae (SFGR). Infection with R. rickettsii can result in serious and life‐threatening illness in people and dogs. Canine seroprevalence has been used as a sentinel for human RMSF in previous studies. This study aims to quantify SFGR seroprevalence in canines in three northern Mexican states and identify risk factors associated with seropositivity. A total of 1,136 serum samples and 942 ticks were obtained from dogs participating in government sterilization campaigns and from animal control facilities in 14 Mexican cities in three states. SFGR antibodies were detected using indirect immunofluorescence antibody assays at titre values ≥1/64. Six per cent (69 dogs) showed antibodies to SFGR, with the highest seroprevalence reported in Baja California (12%), Coahuila (4%) and Sonora (4%). Dogs from Baja California had three times higher odds of having SFGR antibodies compared to dogs from Sonora (OR = 3.38, 95% CI, 1.81–6.37). Roughly one quarter (25%) of surveyed dogs were parasitized by ticks (Rhipicephalus sanguineus sensu lato) at the time of sample collection. A portion of collected ticks were tested for rickettsial DNA using polymerase chain reaction. Positive samples were then sequenced, showing evidence of SFGR including R. massiliae, R. parkeri and R. rickettsii. Dogs that spent the majority of time on the street, such as free‐roaming or community‐owned dogs, showed a greater risk of tick infestation, seropositivity, bearing seropositive ticks, and may play a pivotal role in the spread of SFGR among communities. Estimating the seroprevalence of SFGR in the canine population can help public health campaigns target high‐risk communities for interventions to reduce human RMSF cases.     

Association of polymorphism in the alpha (1,2) fucosyltransferase gene with growth performance in two Western pig breeds in Taiwan

The mutation at 307 bp (M307) of the alpha (1,2) fucosyltransferase gene has been proposed as being a marker for selection of E. coli F18 adhesion-resistant pigs. Nonetheless, exactly how this mutation affects pigs' growth performance remains unclear. This study investigated genotypic frequencies and the effect of M307 and the ryanodine receptor (RYR1) on the growth performance of two major Western pig breeds in Taiwan. In total, 1510 (1024 Duroc and 486 Landrace) boars were performance tested using segregated early weaning entrance. The genotypes of M307 and RYR1 were determined by polymerase chain reaction-based restriction fragment length polymorphism. The performance traits included average daily gain, the feed conversion ratio, backfat thickness, and age at 110 kg of body weight. The statistical model included starting age, test season, genotype of M307, genotype of RYR1, and two- and three-way interactions. The data were analyzed within breeds. Consequently, the genotypic frequencies of the AA genotype in M307 were 0.06 and 0.06, and of the GG genotype were 0.53 and 0.64 in Duroc and Landrace pigs, respectively. The genotypic frequencies of the NN genotype in RYR1 were 0.75 and 0.99, and of the nn genotype were 0.01 and 0.00 in Duroc and Landrace pigs, respectively. There was no significant effect of the M307 genotype on the growth performance in either Duroc or Landrace breeds. However, the RYR1 significantly influenced the average daily gain and age at 110 kg of body weight of Duroc pigs. The results suggest that selection of the favorable AA genotype at M307 for E. coli F18 adhesion resistance may not affect the growth performance traits in Duroc and Landrace pigs. However, the effect of the RYR1 on growth performance should be monitored during selection.