Changes in immune system and intestinal bacteria of cows during the transition period

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Transitional high-energy diets reduce peripheral blood lymphocytes in dairy cows.

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High-energy diets upregulate IL-1β and IL-2 and downregulate IL-10 expression.

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Functional lactobacillus plantarum LP1 restores normal levels of lymphocytes subset.

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Lactobacillus plantarum LP1-added diets reduce inflammatory cytokine expression.

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LP1 mitigates immune response imbalances caused by transitional high energy diets.

High-yield dairy cows need high energy feed during periods of increased milk production. The transitional feeding to high energy feed increases the risk of developing a variety of metabolic disorders. Here, five Holstein cows were fed a four-stage feeding protocol (3 weeks for each stage) ranging from 54.9 to 73.7% total digestive nutrients (TDN). The purpose of the study was to investigate the effect of lactic acid bacteria on high-energy-fed cows associated with transitional feeding, and to evaluate the effects of probiotics on intestinal bacterial changes and inflammatory responses. Three feed transition periods were established for five cows, and Lactobacillus plantarum RGU-LP1 (LP1) was fed as a probiotic during the high-energy feeding period. The number of lymphocyte subsets such as CD3-, CD4-, and CD8 positive cells decreased in response to the high energy feed. Lipopolysaccharide (LPS)-induced cytokine (IL-1β and IL-2) gene expression in peripheral blood mononuclear cells (PBMCs) was shown to increase in those animals receiving the high energy feed. However, supplementation with LP1 resulted in an increase in the number of lymphocyte subsets and the expression of IL-1β and IL-2 were returned to the level at low energy diet. These results suggest that high energy diets induce inflammatory cytokine responses following LPS stimulation, and that the addition of LP1 mitigates these results by regulating the LPS-induced inflammatory reaction. Therefore, the functional lactic acid bacteria LP1 is expected to regulate inflammation resulting from high energy feeding, and this probiotic could be applied to support inflammatory regulation in high-yield dairy cows.

Annotated normal CT data of the abdomen for deep learning: Challenges and strategies for implementation

PURPOSE

The purpose of this study was to report procedures developed to annotate abdominal computed tomography (CT) images from subjects without pancreatic disease that will be used as the input for deep convolutional neural networks (DNN) for development of deep learning algorithms for automatic recognition of a normal pancreas.

MATERIALS AND METHODS

Dual-phase contrast-enhanced volumetric CT acquired from 2005 to 2009 from potential kidney donors were retrospectively assessed. Four trained human annotators manually and sequentially annotated 22 structures in each datasets, then expert radiologists confirmed the annotation. For efficient annotation and data management, a commercial software package that supports three-dimensional segmentation was used.

RESULTS

A total of 1150 dual-phase CT datasets from 575 subjects were annotated. There were 229 men and 346 women (mean age: 45±12years; range: 18-79years). The mean intra-observer intra-subject dual-phase CT volume difference of all annotated structures was 4.27mL (7.65%). The deep network prediction for multi-organ segmentation showed high fidelity with 89.4% and 1.29mm in terms of mean Dice similarity coefficients and mean surface distances, respectively.

CONCLUSIONS

A reliable data collection/annotation process for abdominal structures was developed. This process can be used to generate large datasets appropriate for deep learning.

Der f 35: An MD-2-like house dust mite allergen that cross-reacts with Der f 2 and Pso o 2

BACKGROUND

Dermatophagoides farinae is a source of airborne house dust mite (HDM) allergens. We elucidated IgE-reactive allergens from D. farinae by two-dimensional immunoblotting-based allergenome analysis, and identified one new allergen, named Der f 35, that possesses IgE-binding capacity comparable to that of Der f 2. The aim of this study was to clarify the allergenic capacity of new HDM allergen Der f 35.

METHODS

We cloned der f 35 from D. farinae mRNA and produced recombinant Der f 35 in Escherichia coli. The IgE-binding capacity of Der f 35 and its cross-reactivity with group 2 allergens from D. farinae and Psoroptes ovis were determined by enzyme-linked immunosorbent assay (ELISA) and ELISA inhibition assays, respectively.

RESULTS

The deduced amino acid sequence for der f 35, which possesses the MD-2-related lipid-recognition domain, showed higher identity with group 2 allergens from P. ovis (61.5%) and Blomia tropicalis (50.7%) than with Der f 2 (40.8%). Der f 35 showed IgE-binding frequencies of 77.5% (31/40) for the native form upon allergenome analysis and 51.4% (18/35) for recombinant structure by ELISA. Der f 35 showed cross-reactivity with Der f 2 and Pso o 2 in reaction with HDM-allergic patients' IgE by ELISA inhibition assay.

CONCLUSION

Der f 35 is a candidate major allergen from D. farinae, which is more similar to group 2 allergens from sheep scab mite and storage mites. Der f 35 could be responsible for the cross-reactivity among group 2 mite allergens.

Experimental evaluation of dual Multiple Aperture Devices for Fluence Field Modulated X-Ray Computed Tomography

Acquisition of CT images with comparable diagnostic power can potentially be achieved with lower radiation exposure than the current standard of care through the adoption of hardware-based fluence-field modulation (e.g. dynamic bowtie filters). While modern CT scanners employ elements such as static bowtie filters and tube-current modulation, such solutions are limited in the fluence patterns that they can achieve, and thus are limited in their ability to adapt to broad classes of patient morphology. Fluence-field modulation also enables new applications such as region-of-interest imaging, task specific imaging, reducing measurement noise or improving image quality. The work presented in this paper leverages a novel fluence modulation strategy that uses "Multiple Aperture Devices" (MADs) which are, in essence, binary filters, blocking or passing x-rays on a fine scale. Utilizing two MAD devices in series provides the capability of generating a large number of fluence patterns via small relative motions between the MAD filters. We present the first experimental evaluation of fluence-field modulation using a dual-MAD system, and demonstrate the efficacy of this technique with a characterization of achievable fluence patterns and an investigation of experimental projection data.

Left Atrial Strain at Different Stages of Myxomatous Mitral Valve Disease in Dogs

Background

Decreased function of the left atrium (LA) is a useful prognostic indicator in dogs with myxomatous mitral valve disease (MMVD). In humans, LA strain is a novel severity indicator of mitral regurgitation, but its clinical utility in dogs has not been confirmed.

Objectives

To examine whether LA strain as evaluated with speckle‐tracking echocardiography is associated with MMVD stage in dogs.

Animals

Fifty‐two client‐owned dogs with MMVD.

Methods

Cross‐sectional study. Dogs were classified as stage B1, B2, C, or D, according to the American College of Veterinary Internal Medicine consensus. Physical examination findings and echocardiographic variables were compared among the groups. To assess the comparative accuracy of echocardiographic variables in identifying dogs with the presence or history congestive heart failure (CHF), receiver operating characteristic curves and multivariate logistic analysis were used.

Results

There were no significant differences in parameters of LA strain between B1 and B2 groups. However, LA longitudinal strain during atrial contraction (ε_A) (median, 19.1%; interquartile range, 15.3–24.3% in B1, 19.6%; 14.1–21.4% in B2, 6.2%; 3.18–11.2% in C/D) and during ventricular systole (ε_S) (32.7%; 28.9–39.2% in B1, 35.6%; 31.7–41.9% in B2, 23.6%; 16.9–26.1% in C/D) were significantly lower in stages C/D than in stages B1 and B2. In multivariate logistic regression analysis, ε_A and peak early diastolic mitral inflow velocity were identified as independent indicators of stage C/D.

Conclusions and Clinical Importance

ε_A was the best predictor of the presence or history of CHF. Further studies are needed to determine the clinical implications of these findings for treatment decisions and prognosis determination.

Prospective study of dental intervention for hematopoietic malignancy

Various chemotherapeutic agents used in patients with hematopoietic malignancy cause serious side effects, including myelosuppression and immunosuppression. Immunosuppression makes patients more susceptible to infection, resulting in an increased risk of infectious complications, including the development of severe septicemia that may be life-threatening. It is necessary for dental staff to be familiar with an appropriate protocol in such cases and to share information about the chemotherapy with a hematologist. To verify the effectiveness of our dental intervention protocol, we conducted a prospective study on the incidence of complications for each myelosuppressive grade of chemotherapy in patients with hematopoietic malignancy. We compared the incidence of complications between treatment P (patients who finished all the dental treatments according to the protocol) and treatment Q (patients who did not) per grade (A, B, C, D) and incidence of systemic or oral findings. We also compared the incidence of oral complication related to the residual teeth between first chemo (patients who were undergoing chemotherapy for the first time) and prior chemo (not the first time). There were significant differences in inflammatory complications between treatment P and treatment Q. We found that both systemic and oral inflammatory complications increased with higher-grade myelosuppressive chemotherapy. Additionally, there was a significant difference between the incidence of oral complications related to the residual teeth between first chemo and prior chemo. Complete implementation of the dental intervention protocol was associated with fewer oral and systemic infectious and inflammatory complications in patients with hematopoietic malignancies undergoing chemotherapy. The incidence of oral and systemic complications also increased with grade of chemotherapy. These results support the validity of our dental intervention protocol. We should pay close attention to the oral state of de novo hematopoietic malignancy patients.

Effectiveness of vitamin A acetate for enhancing the production of lung cancer specific monoclonal antibodies

The antibody productivity of the human-human hybridoma cell line AE6, which produces the lung cancer specific human monoclonal antibody AE6F4, was enhanced fourfold upon stimulation with 1 mug/ml of vitamin A acetate for one day. The enhancement lasted for about two weeks, and could be repeated by another stimulation with vitamin A acetate. The enhancing effect of vitamin A acetate was influenced by the cell density. Enhancement was clearly observed when the cell density was under 10(6) cells/ml. However, when the cell density was over 10(7) cells/ml, enhancement was observed weakly or not at all. Although the enhancing effect of vitamin A acetate is not unique to AE6 cells, not all human-human hybridoma cell lines show increased productivity upon VA acetate stimulation. This study suggests that the response to vitamin A acetate may be related to the properties of a particular fusion partner which the hybridoma cell inherits. The efficacy of vitamin A acetate for production of human monoclonal antibodies using human-human hybridomas is discussed.

Antibacterial Activity of Ethanol Extract of Betel Leaf (Piper betle L.) Against Some Food Borne Pathogens

The ethanol extract of Betel leaf (Piper betle L.), an indigenous climber plant of Bangladesh was screened for its antibacterial activity against some foodborne pathogens viz. Vibrio cholerae ATCC 6395, E. coli ATCC 25922,  E. coli O157:H7 NCTC 12049, Shigella dysenteriae-1 MJ-84 and Staphylococcus aureus ATCC 25923. Experimental  findings revealed that the ethanol extract of betel leaves potentially inhibit the growth of these foodborne  pathogens. Minimum inhibitory concentration (MIC) was ranged from 0.625% (w/v) to 0.75% (w/v). The  ethanol extract of betel leaf showed the highest MIC values for E. coli ATCC 25922 (0.625 mm), Vibrio cholera ATCC 6395 (0.625 mm), and Staphylococcus aureus ATCC 25923 (0.625 mm). It was revealed that the antibacterial  activity was highest at around neutral pH and at moderate temperature. The highest temperature (100°C)  and the pH (10.0) treated ethanol extract showed a little less activity than the maximum activity at moderate  temperature and at neutral pH, suggesting that the ethanol extract of the betel leaf was to some extent high  temperature and high pH tolerant. The ethanol extract of betel leaf might have a potential application as  natural food preservative to improve the microbiological safety of the foods. DOI: http://dx.doi.org/10.3329/bjm.v28i2.11817 Bangladesh J Microbiol, Volume 28, Number 2, December 2011, pp 58-63

[Is emergency aortic root replacement combined with arch replacement safe?]

BACKGROUND

Aortic root replacement (ARR) combined with aortic arch replacement (AAR) is an invasive procedure even in elective cases. Nevertheless, such combined operations are often mandatory in acute type A aortic dissection. We examined whether emergency operation might have further incremental risks compared with elective surgery in this type of operations.

METHODS

Forty-six cases of ARR combined with AAR were divided into 2 groups, the emergency (EM) group and the elective (EL) group. The EM group consisted of 10 cases of acute type A aortic dissection, whereas the EL group of 36:23 of chronic aortic dissection and 13 of true aneurysm.

RESULTS

There were no statistical differences between the 2 groups in the durations of aortic crossclamp, selective cerebral perfusion and cardiopulmonary bypass. The incidences in the EM and EL groups were as follows:in-hospital death; 0 vs 3( 8%), respiratory failure; 4 (40%) vs 14 (39%), renal failure; 0 vs 6 (17%), IABP requirement; 1 (10%) vs 3 (8%), and cerebral infarction; 0 vs 1 (3%), respectively.

CONCLUSION

Early surgical results of emergency ARR combined with AAR were almost equal to those in elective surgery.

Twelve oxo-eicosatetraenoic acid induces fetal membrane release after delivery in cows

Fetal fibroblast cell culture from cotyledons of bovine placenta and animal experiments close to term were used to elucidate afterbirth release and factors missing in the signal transduction mechanism for retained fetal membranes (RFM) after delivery. In cell culture the addition of arachidonic acid (Ara) to the medium caused rapid release to free floating cell in the culture dish, accompanied by matrix metalloproteinase (MMP) activation, being consistent with previous in vivo observations, where a relation between MMP and fetal membrane release had been shown. Ara-induced cell floating was not inhibited by the addition of cyclooxygenase (COX) inhibitor, and not induced by the addition of PGF2α or PGE2 to replace Ara, while 12-lipoxygenase (12-LOX) metabolite of Ara, 12-oxo-eicosatetraenoic acid (12-oxoETE), strongly induced cell floating. In the animal experiments, 12-oxoETE injection to delivery-induced cows (n = 6) using prostaglandin (PG) and dexamethazone resulted in rapid release of fetal membranes. In cows with natural calf delivery, a 12-oxoETE peak (11.7-16.8 ng/ml) was observed in maternal blood plasma prior to release of fetal membranes. This investigation thus gives new indications for that the mediator for fetal membrane release is 12-oxoETE and not PG.

Quantitative evaluation of cryptococcal pathogenesis and antifungal drugs using a silkworm infection model with Cryptococcus neoformans

AIMS

To develop an in vivo system that could quantitatively evaluate the therapeutic effects of antifungal drugs using a silkworm infection model with Cryptococcus neoformans.

METHODS AND RESULTS

Silkworms reared at 37°C died after an injection of viable serotype A C. neoformans fungus into the haemolymph. The serotype A C. neoformans, which is known to have higher mammal pathogenicity than the serotype D, was also more virulent against the silkworm. Furthermore, the deletion mutants of genes gpa1, pka1 and cna1, which are genes known to be necessary for the pathogenesis in mammals, showed an increase in the number of fungal cells necessary to kill half of the silkworm population (LD(50) value). Antifungal drugs, amphotericin B, flucytosine, fluconazole and ketoconazole, showed therapeutic effects in silkworms infected with C. neoformans. However, amphotericin B was not therapeutically effective when injected into the silkworm intestine, comparable to the fact that amphotericin B is not absorbed by the intestine in mammals.

CONCLUSIONS

The silkworm-C. neoformans infection model is useful for evaluating the therapeutic effects of antifungal drugs.

SIGNIFICANCE AND IMPACT OF THE STUDY

The silkworm infection model has various advantages for screening antifungal drug candidates. We can also elucidate the cryptococcal pathogenesis and evaluate the in vivo pharmacokinetics and toxicity of each drug.

Properties of ras-amplified recombinant BHK-21 cells in protein-free culture

We compared serum and protein-free cultures ofa ras-amplified recombinant BHK-21 cell line(ras-rBHK-IgG), which hyperproduces a lungcancer specific recombinant human monoclonal antibody. Ras-rBHK-IgG cells were shown to grow well, evenin protein-free medium and to be morphologicallysimilar to cells cultured in serum containing medium. However, the growth rate of ras-rBHK-IgG cellswas considerably slower in protein-free medium, whichresults in a longer maintenance period compared with cells cultured in serum containing medium. In addition, it was found that antibody production in protein-free culture had a ten times higher maximum than cells cultured in serum containing medium. On theother hand, in high density culture, using the hollowfiber bioreactor system, ras-rBHK-IgG cellscould be maintained for a month in protein-freeculture in contrast with serum culture, which onlylasted for half a month. However, the markedincrease of antibody production was not observed. A total amount of about 15 mg of the recombinantantibody, obtained in protein-free culture, was abouttwo times of that obtained in serum culture, and wasshown to be reactive to lung cancer cells in tissue. From these properties in protein-free medium, it isconcluded that protein-free culture of ras-rBHK-IgG cells is suitable for middle scaleproduction of recombinant human monoclonal antibody.

Practical evaluation of Mung bean seed pasteurization method in Japan

The majority of the seed sprout-related outbreaks have been associated with Escherichia coli O157:H7 and Salmonella. Therefore, an effective method for inactivating these organisms on the seeds before sprouting is needed. The current pasteurization method for mung beans in Japan (hot water treatment at 85 degrees C for 10 s) was more effective for disinfecting inoculated E. coli O157:H7, Salmonella, and nonpathogenic E. coli on mung bean seeds than was the calcium hypochlorite treatment (20,000 ppm for 20 min) recommended by the U.S. Food and Drug Administration. Hot water treatment at 85 degrees C for 40 s followed by dipping in cold water for 30 s and soaking in chlorine water (2,000 ppm) for 2 h reduced the pathogens to undetectable levels, and no viable pathogens were found in a 25-g enrichment culture and during the sprouting process. Practical tests using a working pasteurization machine with nonpathogenic E. coli as a surrogate produced similar results. The harvest yield of the treated seed was within the acceptable range. These treatments could be a viable alternative to the presently recommended 20,000-ppm chlorine treatment for mung bean seeds.

Leakage of intracellular UV materials of high hydrostatic pressure-injured Escherichia coli O157:H7 strains in tomato juice

The behavior of high hydrostatic pressure-injured Escherichia coli O157:H7 cells (strain SEA13B88 and a strain from the June-July 1999 Oklahoma juice outbreak) in tomato juice (pH 4.1) and phosphate-buffered saline (PBS; pH 7.2) at final concentrations of 8.4 to 8.8 log CFU/ml, respectively, and treated at 400, 500, and 600 MPa for 40 min at 25 and 35 degrees C with storage at 5 and 23 degrees C for 1,800 min was investigated. Immediately after treatment and every 3 h for 24 h of storage, an aliquot (0.1 ml) was plated on Trypticase soy agar and sorbitol MacConkey agar to determine the percentage of injured population. Leakage of UV materials and possible recovery from injury were investigated. Pressure (600-MPa) treatment at 35 degrees C for 40 min caused a higher percentage of bacterial injury than for 10 min of treatment. A higher percentage of injured population was found among the Oklahoma strain cells than among strain SEA13B88 cells, and differences in viability loss for bacterial strains were determined. The viability loss determined in PBS was 4.8 log for SEA13B88 cells and 5.2 log for Oklahoma cells, while losses of 5.4 and 5.7 log were determined in tomato juice for SEA13B88 and Oklahoma cells, respectively. The leakage of intracellular materials of injured Oklahoma cells was higher than that observed for SEA13B88 cells, but injured Oklahoma cells recovered faster in PBS. However, injured and healthy populations for both strains were below detection in tomato juice stored at 5 degrees C for 1,440 min.

Peculiar clusters of daughter cells observed in Cryptococcus neoformans grown in sealed microtiter plates

Cryptococcus neoformans was grown in 96-well microtiter plates sealed by foil which is less than 0.01 % permeable to oxygen. On day 14 of the cultivation, we observed peculiar clusters of small droplike daughter cells arranged around < or = 4 % of mother cells. The fact that most of the other cells had died indicates that few cells had been able to survive hypoxic conditions and escape the cell-cycle arrest. However, their daughters were unable to separate from them and to continue their proliferation under such conditions.

Thermal destruction of Escherichia coli O157:H7 in sous-vide cooked ground beef as affected by tea leaf and apple skin powders

We investigated the heat resistance of a four-strain mixture of Escherichia coli O157:H7 in raw ground beef in both the absence and presence of white and green tea powders and an apple skin extract. Inoculated meat was cooked using the sous-vide technique, i.e., the meat was packaged in sterile bags and completely immersed in a circulating water bath at low temperature for a period of time. The bags were cooked for 1 h to an internal temperature of 55, 58, 60, or 62.5 degrees C, and then held from 240 min at 55 degrees C to 10 min at 62.5 degrees C. The surviving bacteria were enumerated by spiral plating onto tryptic soy agar overlaid with sorbitol-MacConkey agar. Inactivation kinetics of the pathogens deviated from first-order kinetics. D-values (time, in minutes, required for the bacteria to decrease by 90%) in the control beef ranged from 67.79 min at 55 degrees C to 2.01 min at 62.5 degrees C. D-values determined by a logistic model ranged from 36.22 (D1, the D-value of a major population of surviving cells) and 112.79 (D2, the D-value of a minor subpopulation) at 55 degrees C to 1.39 (D1) and 3.00 (D2) at 62.5 degrees C. A significant increase (P < 0.05) in the sensitivity of the bacteria to heat was observed with the addition of 3% added antimicrobials. D-value reductions of 62 to 74% were observed with apple powder and 18 to 58% with tea powders. Thermal death times from this study will assist the retail food industry to design cooking regimes that ensure the safety of beef contaminated with E. coli O157:H7.

Combination treatments for killing Escherichia coli O157:H7 on alfalfa, radish, broccoli, and mung bean seeds

In this study, the effectiveness of prolonged dry-heat treatment (50 degrees C) alone or in combination with chemical treatments (1% oxalic acid, 0.03% phytic acid, 50% ethanol, electrolyzed acidic water, and electrolyzed alkaline water) in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, broccoli, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. Dry-heat treatment for 17 or 24 h alone could reduce E. coli O157:H7 numbers to below detectable levels in radish, broccoli, and alfalfa seeds, but was unable to reduce the pathogen numbers to below the detectable level in mung bean seeds. In addition, dry-heat treatment for 17 h plus sanitizer treatments were effective in greatly reducing pathogen populations on radish, broccoli, and alfalfa seeds, without compromising the quality of the sprouts, but these treatments did not eliminate the pathogen from radish and alfalfa seeds. Seventeen hours of dry heat followed by a 1.0-kGy dose of irradiation completely eliminated E. coli O157:H7 from radish and mung bean seeds, whereas only a minimum radiation dose of 0.25 kGy was required to completely eliminate the pathogen from broccoli and alfalfa seeds. Dry heat in combination with radiation doses of up to 1.0 kGy did not negatively impact the seed germination rate or length of alfalfa, broccoli, and radish seeds or the length of alfalfa, broccoli, and radish sprouts, but did decrease the length of mung bean sprouts.

Genetic diversity of longtail macaques (Macaca fascicularis) on the island of Mauritius: an assessment of nuclear and mitochondrial DNA polymorphisms

BACKGROUND

Individuals from an introduced population of longtail macaques on Mauritius have been extensively used in recent research. This population has low MHC gene diversity, and is thus regarded as a valuable resource for research.

METHODS

We investigated the genetic diversity of this population using multiple molecular markers located in mitochondrial DNA and microsatellite DNA loci on the autosomes and the Y chromosome. We tested samples from 82 individuals taken from seven study sites.

RESULTS AND CONCLUSIONS

We found this population to be panmictic, with a low degree of genetic variability. On the basis of an mtDNA phylogeny, we inferred that these macaques' ancestors originated from Java in Asia. Weak gametic disequilibrium was observed, suggesting decay of non-random associations between genomic genes at the time of founding. The results suggest that macaques bred in Mauritius are valuable as model animals for biomedical research because of their genetic homogeneity.

Hot water treatments to inactivate Escherichia coli O157:H7 and Salmonella in mung bean seeds

The majority of the seed sprout-related outbreaks have been associated with Escherichia coli O157:H7 and Salmonella. Therefore, an effective method is needed to inactivate these organisms on the seeds before they are sprouted. This study was conducted to assess the effectiveness of various hot water treatments to inactivate E. coli O157:H7 and Salmonella populations on mung beans seeds intended for sprout production and to determine the effect of these treatments on seed germination after the seeds were dipped in chilled water for 30 s. Mung bean seed inoculated with four-strain cocktails of E. coli O157:H7 and Salmonella were soaked into hot water at 80 and 90 degrees C with shaking for various periods and then dipped in chilled water for 30 s. The treated seeds were then assessed for the efficacy of the treatment for reducing populations of the pathogens and the effects of the treatment on germination. After inoculation and air drying, 6.08 +/- 0.34 log CFU/g E. coli O157:H7 and 5.34 +/- 0.29 log CFU/g Salmonella were detected on the seeds. After hot water treatment at 90 degrees C for 90 s followed by dipping in chilled water for 30 s, no viable pathogens were found and no survivors were found in the enrichment medium and during the sprouting process. The germination yield of the seed was not affected significantly. Therefore, hot water treatment followed by dipping in chilled water for 30 s could be an effective seed decontamination method for mung bean seeds intended for sprout production.

Effect of mechanical processing of corn silage on in vitro ruminal fermentation, and in situ bacterial colonization and dry matter degradation

Rumen fermentation and bacterial colonization of mechanically processed corn silage were evaluated in a series of in vitro and in situ experiments using ruminally cannulated cows. Data from rumen-simulated continuous culture (Rusitec) showed that total VFA concentration was increased (P < 0.001) by feeding processed corn silage, while pH was reduced (P < 0.001) and ammonia nitrogen remained unchanged (P > 0.05). Mechanical processing enhanced the in situ rate and extent of dry matter disappearance for corn stems and kernels, respectively (P < 0.05). It also enhanced in situ, the initial attachment of rumen bacteria responsible for corn digestion, as monitored by real-time PCR. The16S rDNA copy numbers of amylolytic and lipolytic bacteria, such as Succinivibrio dextrinosolvens, Ruminobacter amylophilus and Anaerovibrio lipolytica, attached to corn kernels were increased for processed corn silage (P < 0.05), in particular at 2 h after the start of incubation. In addition, corn stemattached cellulolytic and hemicellulolytic bacteria, such as Fibrobacter succinogenes, ruminococci and Eubacterium ruminantium, increased in 16S rDNA copy numbers for processed corn silage (P < 0.05). This was observed for the initial incubation period from 10 min to 2 h. These results demonstrate more rapid attachment and heavier colonization of rumen bacteria to the processed compared with the unprocessed silage, which facilitates ruminal digestion and fermentation. Key words: Corn silage, mechanical processing, rumen fermentation, bacteria, attachment

Control of Clostridium perfringens spores by green tea leaf extracts during cooling of cooked ground beef, chicken, and pork

We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by two green tea extracts with low (green tea leaf powder [GTL]; 141 mg of total catechins per g of green tea extract) and high (green tea leaf extract [GTE]; 697 mg of total catechins per g of extract) catechin levels during abusive chilling of retail cooked ground beef, chicken, and pork. Green tea extracts were mixed into the thawed beef, chicken, and pork at concentrations of 0.5, 1.0, and 2.0% (wt/ wt), along with a heat-activated (75 degrees C for 20 min) three-strain spore cocktail to obtain a final concentration of approximately 3 log spores per g. Samples (5 g) of the ground beef, chicken, and pork were then vacuum packaged and cooked to 71 degrees C for 1 h in a temperature-controlled water bath. Thereafter, the products were cooled from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h, resulting in significant increases (P < 0.05) in the germination and outgrowth of C. perfringens populations in the ground beef, chicken, and pork control samples without GTL or GTE. Supplementation with 0.5 to 2% levels of GTL did not inhibit C. perfringens growth from spores. In contrast, the addition of 0.5 to 2% levels of GTE to beef, chicken, and pork resulted in a concentration-and time-dependent inhibition of C. perfringens growth from spores. At a 2% level of GTE, a significant (P < 0.05) inhibition of growth occurred at all chill rates for cooked ground beef, chicken, and pork. These results suggest that widely consumed catechins from green tea can reduce the potential risk of C. perfringens spore germination and outgrowth during abusive cooling from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h of cooling for ground beef, chicken, and pork.

Histone H1 vaccine therapy for overcoming acute rejection in experimental organ transplantation

OBJECTIVE

In a rat tolerogenic orthotopic liver transplantation (OLT) model, the recipient serum (post-OLT serum) shows strong immunosuppressive activity. In our previous reports, we suggested that autoreactive antibody (Ab) against histone H1 is a major immunosuppressive factor in this serum. The present study sought to determine whether up-regulation of anti-histone H1 Ab by histone H1 vaccination led to tolerance.

MATERIALS AND METHODS

Using mixed lymphocyte reactions (MLR) and heterotopic heart transplantations (HHT), the alloreactive T-cell responses and allograft survivals of histone H1-immunized rats were compared with those of control rats. Cytokine and cellular profiles were determined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry.

RESULTS

The alloreactive T-cell response of histone H1-immunized rats was significantly lower than that of control rats, although there was no difference in nonspecific T-cell activation between the 2 groups. The allograft survival of histone H1-immunized rats was significantly prolonged after HHT. The major histocompatibility complex (MHC) class II and CD25 molecules of histone H1-immunized rats were significantly down-regulated compared with those of control rats. Moreover, the serum cytokine profile was modified by the immunization with histone H1.

CONCLUSIONS

These results suggest that histone H1 vaccination of transplant recipients leads to the production of immunosuppressive factors and the modification of cytokine/cellular profiles.

Irradiation inactivation of Listeria monocytogenes in low-fat ground pork at freezing and refrigeration temperatures

Gamma radiation effectively controls Listeria monocytogenes in uncooked and in ready-to-eat foods. This study was conducted to determine if gamma radiation could be used to control L. monocytogenes in ground pork. Ground pork was contaminated with L. monocytogenes, kept at refrigeration (4 degrees C), chilling (0 degrees C), and freezing (-18 degrees C) temperatures overnight, exposed to gamma radiation and stored at 4 degrees C for 7 days, and at 0 and -18 degrees C for 60 days. Following irradiation, the meat was assayed for L. monocytogenes viable counts and lipid oxidation. A triangle test was performed to determine if sausage made from the irradiated and nonirradiated ground pork differed in sensory quality. It was observed that a 5-log reduction of L. monocytogenes viable counts would require a 3.0-kGy radiation dose. The results of a 60-day storage study of ground pork inoculated with 10(5) to 10(6) CFU of L. monocytogenes per gram indicated that counts for nonirradiated meat remained fairly constant at refrigeration, chilling, and freezing temperatures. However, irradiation of ground pork at 3.0 kGy could inactivate L. monocytogenes totally in ground pork subsequently held at all the temperatures used in this study. Lipid oxidation measurements, as determined by the thiobarbituric acid-reactive substance assay, ranged from 0.16 nmol/g for nonirradiated ground pork and 0.20 nmol/g for meat irradiated at 3.0 kGy. Sensory panelists could distinguish between irradiated and nonirradiated sausage but were divided on whether irradiation adversely affected the sausage quality. Our results suggest that gamma radiation could be useful to control L. monocytogenes in ground pork and improve the safety of ground pork products.

Role of Antinuclear Antibodies in Experimental and Clinical Liver Transplantation

OBJECTIVE

We recently reported that autoreactive antibodies (Abs) against nuclear histone H1 was transiently induced at an early phase after orthotopic liver transplantation (OLT) in a tolerogenic rat OLT model and possessed immunosuppressive activity. It was also reported that nuclear antigen, high-mobility group box 1 (HMGB1) protein was one of the initiators of the immune reaction. The present study sought to evaluate the role of antinuclear Abs in experimental and clinical liver transplantation.

MATERIALS AND METHODS

We prepared 3 animal models: natural tolerance model (DA liver into PVG); acute rejection model (DA liver into LEW); and drug-induced tolerance model (acute rejection model + cyclosporine [CsA]). In addition, we examined clinical samples, including 1 drug-free patient, to measure the antihistone H1/HMGB1 titers at various times after OLT.

RESULTS

In a natural tolerance model, antihistone H1 and HMGB1 Ab was induced during the rejection and the tolerance induction phases, respectively. Those Ab responses were also confirmed in a drug-induced tolerance model, whereas no such responses were shown in an acute rejection model. In our clinical drug-free patient, antihistone H1/HMGB1 titer was significantly higher after cessation of CsA than that in healthy volunteers.

CONCLUSIONS

Antinuclear Ab is actively expressed in accordance with overcoming rejection episodes with subsequent tolerance induction in both a natural tolerance model and a drug-induced tolerance model. We also observed a similar tendency in our clinical drug-free patient. These results suggested that antinuclear Abs may be useful markers to determine the timing to withdraw immunosuppressants.

Characterization of Bacillus subtilis strains in Thua nao, a traditional fermented soybean food in northern Thailand

AIMS

To clarify the diversity of Bacillus subtilis strains in Thua nao that produce high concentrations of products useful in food manufacturing and in health-promoting compounds.

METHOD AND RESULTS

Production of amylase, protease, subtilisin NAT (nattokinase), and gamma-polyglutamic acid (PGA) by the Bacillus subtilis strains in Thua nao was measured. Productivity of protease NAT by these strains tended to be higher than by Japanese commercial natto-producing strains. Molecular diversity of isolated strains was analysed via randomly amplified polymorphic DNA-PCR fingerprinting. The strains were divided into 19 types, including a type with the same pattern as a Japanese natto-producing strain.

CONCLUSION

B. subtilis strains that could be a resource for effective production of protease, amylase, subtilisin NAT, or PGA were evident in Thua nao produced in various regions in northern Thailand.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study clearly demonstrated the value of Thua nao as a potential resource of food-processing enzymes and health-promoting compounds.

Oral administration of pulverized Konjac glucomannan prevents the increase of plasma immunoglobulin E and immunoglobulin G levels induced by the injection of syngeneic keratinocyte extracts in BALB/c mice

BACKGROUND

Immunoglobulin (Ig) E plays a key role in the pathogenesis of atopic diseases, such as asthma, atopic dermatitis and allergic rhinitis. Oral administration of pulverized Konjac glucomannan (PKGM) has recently been demonstrated to prevent both plasma IgE elevation and developing dermatitis in NC/Nga mice, a model of atopic dermatitis.

OBJECTIVE

To clarify the direct effect of PKGM on the increase of plasma IgE, we employed the system of BALB/c mouse that increases IgE level without developing dermatitis in response to continuous injection of the extract of syngeneic keratinocytes, PAM 212 cells (PAM extract).

METHODS

Three weeks after the start of feeding with either control or PKGM diet, mice were injected subcutaneously with PAM extract bi-weekly for 10 weeks. The levels of plasma Igs were measured by enzyme-linked immunosorbent assay every 2 weeks after the injection. The levels of epsilon germline transcription and the amounts of mRNA for IL-4, IFN-gamma, GATA-3 and T bet gene in the spleen were evaluated by real-time RT-PCR at the end of the experiment.

RESULTS

On the one hand, PKGM prevented the increase of plasma IgE and IgG (IgG1, IgG2b) induced by PAM extract, and on the other hand, it enhanced the levels of plasma IgG3. However, it did not affect the level of plasma IgM. PKGM also reduced the levels of plasma ovalbumin (OVA)-specific IgE in OVA-sensitized mice. Moreover, PKGM attenuated the induction of epsilon germline transcription and expression levels of mRNA for IL-4, IFN-gamma and GATA-3 in the spleen of PAM extract-injected mice. PKGM also attenuated the induction of epsilon germline transcription and mRNA for IFN-gamma and T bet in the spleen of phosphate-buffered saline-injected control mice.

CONCLUSIONS

These results suggested that oral administration of PKGM prevents the elevation of plasma IgE by suppressing IgE class switching in B cells and/or the commitment development of naive lymphocytes to both T-helper type 1 (Th1) and Th2.

MDCT angiography of living laparoscopic renal donors

Laparoscopic donor nephrectomy has become the accepted method of harvesting the kidney at many institutions because of multiple advantages over open donor nephrectomy. Spiral computed tomographic (CT) angiography provides accurate information of renal vascular anatomy and has become an accepted method of preoperative evaluation of potential laparoscopic renal donors. More recently, multidetector CT (MDCT) provides more detailed datasets compared with single-detector spiral CT and has been used for preoperative evaluation of laparoscopic donor nephrectomy to provide accurate anatomic information. MDCT (especially 16- and 64-slice MDCT) angiography has advantages over single-detector helical CT due to rapid scan time that allows coverage of a large volume of interest with higher spatial and temporal resolutions. In this article, we review the current status of MDCT angiography in the evaluation of laparoscopic renal donors and potential advantages of using this technology.

Identification of differentially expressed genes in psoriasis using expression profiling approaches

To identify differentially expressed genes which play causal roles in pathogenesis and maintenance for psoriasis, we used BodyMapping and introduced amplified fragment length polymorphism approaches. From the BodyMap database, we selected 2007 genes which specifically expressed in epithelial tissues. Among 2007 genes, we surveyed genes which differentially expressed in involved or uninvolved psoriatic lesional skin samples compared with atopic dermatitis, mycosis fungoides, and normal skin samples. As a result of surveying 2007 genes, 241 genes were differentially expressed only in involved psoriatic skin but not in the other samples. Hierarchical cluster analysis of gene expression profiles showed that 13 independent psoriatic-involved skin samples clustered tightly together, reflecting highly similar expression profiles. Using the same 2007 gene set, we examined gene expression levels in five serial lesions from distal uninvolved psoriatic skin to involved psoriatic plaque. We identified seven genes such as alpha-1-microglobulin/bikunin precursor, calnexin, claudin 1, leucine zipper down-regulated in cancer 1, tyrosinase-related protein 1, Yes-associated protein 1, and unc-13-like protein (Coleonyx elegans) which show high-expression levels only in uninvolved psoriatic lesions. These seven genes, which were reported to be related to apoptosis or antiproliferation, might have causal roles in pathophysiology in psoriasis.

Use of hydrogen peroxide in combination with nisin, sodium lactate and citric acid for reducing transfer of bacterial pathogens from whole melon surfaces to fresh-cut pieces

Hydrogen peroxide (2.5%) alone or hydrogen peroxide (1%) in combination with nisin (25 microg/ml), sodium lactate (1%), and citric acid (0.5%) (HPLNC) were investigated as potential sanitizers for reducing Escherichia coli O157:H7 or Listeria monocytogenes populations on whole cantaloupe and honeydew melons. Whole cantaloupes inoculated with E. coli O157:H7 and L. monocytogenes at 5.27 and 4.07 log10 CFU/cm2, respectively, and whole honeydew melons inoculated with E. coli O157:H7 and L. monocytogenes at 3.45 and 3.05 log10 CFU/cm2, respectively, were stored at 5 degrees C for 7 days. Antimicrobial washing treatments were applied to inoculated whole melons on days 0 or 7 of storage and surviving bacterial populations and the numbers transferred to fresh-cut pieces were determined. At days 0 and 7 treatment with HPLNC significantly (p<0.05) reduced the numbers of both pathogens, by 3 to 4 log CFU/cm2 on both types of whole melon. Treatment with HPLNC was significantly (p<0.05) more effective than treatment with 2.5% hydrogen peroxide. While fresh-cut pieces prepared from stored whole melons were negative for the pathogens by both direct plating and by enrichment, fresh-cut pieces from cantaloupe melons treated with 2.5% hydrogen peroxide were positive for both pathogens and pieces from honeydew melons were positive for E. coli 0157:H7. The native microflora on fresh-cut melons were also substantially reduced by HPLNC treatment of whole melons. The results suggest that HPLNC could be used to decontaminate whole melon surfaces and so improve the microbial safety and quality of fresh-cut melons.

Modeling the pressure inactivation dynamics of Escherichia coli

Escherichia coli, as a model microorganism, was treated in phosphate-buffered saline under high hydrostatic pressure between 100 and 300 MPa, and the inactivation dynamics was investigated from the viewpoint of predictive microbiology. Inactivation data were curve fitted by typical predictive models: logistic, Gompertz and Weibull functions. Weibull function described the inactivation curve the best. Two parameters of Weibull function were calculated for each holding pressure and their dependence on holding pressure was obtained by interpolation. With the interpolated parameters, inactivation curves were simulated and compared with the experimental data sets.

Combined efficacy of nisin and pediocin with sodium lactate, citric acid, phytic acid, and potassium sorbate and EDTA in reducing the Listeria monocytogenes population of inoculated fresh-cut produce

The inability of chlorine to completely inactivate human bacterial pathogens on whole and fresh-cut produce suggests a need for other antimicrobial washing treatments. Nisin (50 microg/ml) and pediocin (100 AU/ml) individually or in combination with sodium lactate (2%), potassium sorbate (0.02%), phytic acid (0.02%), and citric acid (10 mM) were tested as possible sanitizer treatments for reducing the population of Listeria monocytogenes on cabbage, broccoli, and mung bean sprouts. Cabbage, broccoli, and mung bean sprouts were inoculated with a five-strain cocktail of L. monocytogenes at 4.61, 4.34, and 4.67 log CFU/g, respectively. Inoculated produce was left at room temperature (25 degrees C) for up to 4 h before antimicrobial treatment. Washing treatments were applied to inoculated produce for 1 min, and surviving bacterial populations were determined. When tested alone, all compounds resulted in 2.20- to 4.35-log reductions of L. monocytogenes on mung bean, cabbage, and broccoli, respectively. The combination treatments nisin-phytic acid and nisin-pediocin-phytic acid caused significant (P < 0.05) reductions of L. monocytogenes on cabbage and broccoli but not on mung bean sprouts. Pediocin treatment alone or in combination with any of the organic acid tested was more effective in reducing L. monocytogenes populations than the nisin treatment alone. Although none of the combination treatments completely eliminated the pathogen on the produce, the results suggest that some of the treatments evaluated in this study can be used to improve the microbial safety of fresh-cut cabbage, broccoli, and mung bean sprouts.

Molecular cloning of a class IV chitinase allergen from Japanese cedar (Cryptomeria japonica) pollen and competitive inhibition of its immunoglobulin E-binding capacity by latex C-serum

BACKGROUND

Japanese cedar (Cryptomeria japonica) pollinosis is one of the most prevalent allergic diseases in Japan. Only three C. japonica allergens, Cry j 1, Cry j 2, and CJP-6, have been characterized. The full IgE-binding spectrum of C. japonica pollen allergens demonstrates that many allergens remain to be identified.

OBJECTIVE

The aim of this study was to characterize a novel allergen with a high frequency of IgE binding.

METHODS

The cDNA coding for a high-frequency IgE-binding protein, designated CJP-4, was cloned from the total mRNA of C. japonica pollen. The corresponding native allergen was purified by affinity precipitation with colloidal chitin and gel chromatography. The IgE-binding ability of purified native CJP-4 was characterized by ELISA and ELISA inhibition.

RESULTS

The CJP-4 cDNA encoded 281 amino acids with significant sequence homology to class IV chitinases. Purified native CJP-4, migrated as a homogeneous 34-kDa protein on SDS-PAGE, revealed endochitinase activity on native PAGE. The purified protein displayed the ability to bind IgE from all patients tested (31/31) in ELISA, whereas Cry j 1 bound to IgE at a 71% frequency (22/31). Pre-incubation with latex C-serum completely inhibited the reaction of pooled sera IgE from patients with C. japonica pollinosis and/or latex allergy to purified CJP-4.

CONCLUSION

We identified CJP-4 as a novel and fourth C. japonica chitinase allergen with high IgE-binding frequency. The competitive IgE-binding profile between C. japonica chitinase and latex C-serum indicated that C. japonica chitinase should be an important pan-allergen in C. japonica pollen.

Effectiveness of irradiation treatments in inactivating Listeria monocytogenes on fresh vegetables at refrigeration temperature

Ionizing radiation can be effective in controlling the growth of food spoilage and foodborne pathogenic bacteria. This study reports on an investigation of the effectiveness of irradiation treatment to eliminate Listeria monocytogenes on laboratory-inoculated broccoli, cabbage, tomatoes, and mung bean sprouts. Irradiation of broccoli and mung bean sprouts at 1.0 kGy resulted in reductions of approximately 4.88 and 4.57 log CFU/g, respectively, of a five-strain cocktail of L. monocytogenes. Reductions of approximately 5.25 and 4.14 log CFU/g were found with cabbage and tomato, respectively, at a similar dose. The appearance, color, texture, taste, and overall acceptability did not undergo significant changes after 7 days of postirradiation storage at 4 degrees C, in comparison with control samples. Therefore, low-dose ionizing radiation treatment could be an effective method for eliminating L. monocytogenes on fresh and fresh-cut produce.