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The ecology of Escherichia coli O157:H7 is not well understood. The aims of this study were to determine the prevalence of and characterize E. coli O157:H7 associated with houseflies (HF). Musca domestica L. HF (n ‫؍‬ 3,440) were collected from two sites on a cattle farm over a 4-month period and processed individually for E. coli O157:H7 isolation and quantification. The prevalence of E. coli O157:H7 was 2.9 and 1.4% in HF collected from feed bunks and a cattle feed storage shed, respectively. E. coli O157:H7 counts ranged from 3.0 ؋ 10 1 to 1.5 ؋ 10 5 CFU among the positive HF. PCR analysis of the E. coli O157:H7 isolates revealed that 90.4, 99.2, 99.2, and 100% of them (n ‫؍‬ 125) possessed the stx1, stx2, eaeA, and fliC genes, respectively. Large populations of HF on cattle farms may play a role in the dissemination of E. coli O157:H7 among animals and to the surrounding environment.Enterohemorrhagic Escherichia coli O157:H7 is a wellknown causative agent of hemorrhagic colitis and hemolytic uremic syndrome in humans. Outbreaks of the food-borne illness caused by E. coli O157:H7 have been reported throughout the northern hemisphere, most frequently in the United States, Canada, Japan, and the United Kingdom. In the United States alone, E. coli O157:H7 causes more than 73,000 cases of human infection every year (11). E. coli O157:H7 strains commonly carry verotoxins (encoded by the stx1 and stx2 genes) and factors for the attachment to the host mucosa, including intimin (encoded by the eaeA gene) (11). The low infectious dose and high virulence of E. coli O157:H7 make infections severe and life-threatening, particularly for young children, the elderly, and those with weakened immune systems (11). The main reservoir for E. coli O157:H7 is the intestinal tracts of healthy cattle. Individual cattle are transiently colonized and shed E. coli O157:H7 in their feces (1). The sources of E. coli O157:H7, which colonizes cattle, are not well understood, and little is known about the ecology of E. coli O157:H7 in the environment (1). Additionally, the high variability in the prevalence of E. coli O157:H7 among cattle suggests the possibility of a reservoir of E. coli O157:H7 external to cattle. However, other than the detection of E. coli O157:H7 in nonbovine animals, including sheep, horses, dogs, and wild birds (1), the ecology of this pathogen has not been extensively studied.One of the potential modes of dissemination of this pathogen in the environment is by insects that are associated with animal feces and manure, primarily houseflies (HF; Musca domestica L.). HF larvae develop in animal feces, including cattle manure. Consequently, HF commonly build up very large populations on cattle farms and in other animal facilities. Previously, a laboratory-based study demonstrated that E. coli O157:H7 ingested by HF remained viable in the fly excreta and that the HF were able to carry and disseminate E. coli for several days (9). In Japan, HF were implicated in the transmission of E. coli O157:H7 from reservoir animals to...

Seawater and organic material (live and/or dead matter deposited on any substratum submersed in seawater) were collected during the cool weather season from a coast of the Seto-Inland Sea, Japan, and analyzed to determine Vibrio parahaemolyticus densities and the occurrence of pathogenic strains, defined as those possessing tdh and/or trh genes by the polymerase chain reaction (PCR), using isolated DNA from enrichment culture of the samples. About 95% of the samples were positive for V. parahaemolyticus (with densities of 3 to >1400 cells per 100 ml water or 10 g organic samples) by the most-probable-number (MPN)-PCR technique with species-specific toxR primers, but only 40% were positive by the conventional MPN-culture technique (with densities ranging from 3 to 240 cells per 100 ml water or 10 g organics). Furthermore, the tdh and trh genes were positive in 55% and 20% of samples, respectively, by the MPN-PCR technique. No tdh and trh gene-positive strains were isolated by the conventional MPN-culture procedure. The difference in detection between the MPN-culture and the MPN-PCR techniques appeared to be significant and may be attributed to different detection sensitivities and other factors.

A test of the suitability of subsurface drip irrigation (SDI) for alfalfa (Medicago sativa L) compared to a sprinkler, was conducted on a Kansas producer's field where the soil is loam. The treatments included drip tape spacing of 60, 40, and 30 inches placed at depths of 18 and 12 inches. A nearby plot irrigated by a center pivot sprinkler was seeded to alfalfa and used for comparison. Seedling emergence and yield were adversely affected at 60 inch spacing, while the depth of placement of drip tapes (18 and 12 inches) showed no effect on yield. The site served for education and allowed comparison between SDI tape spacing and center pivot system.

The persistence of DNA after the cell death causes a major issue in aspects of medical or biological studies. The signal from viable bacterial cells cannot be distinguished from the dead cells in the conventional DNA-based detection methods. In the present study, the loop-mediated isothermal amplification (LAMP) method combined with the ethidium monoazide (EMA) treatment was applied for specific detection of viable, but not dead, Salmonella cells. For this method (EMA-LAMP), we designed a series of primers, which recognize six distinct sequences of the target invA gene conserved in Salmonella. The invA gene of the viable cells was remarkably amplified within 1 hr when as small amounts as 100 fg of DNA was subjected to EMA-LAMP. Because EMA selectively penetrated into the dead cells and bound covalently to DNA, the gene of the dead cells could not be amplified. This study offers a novel DNA-based method to distinguish the viable bacterial cells from the dead cells.

A study was conducted to compare the survival, production and economics of mud crab fattening in cage with fattening in encircled earthen brackishwater pond. Thirty cages of 1m (L) × 1m (W) × 0.3m (H) partitioned into 16 compartments (each 25 × 25 × 30 cm) were set in a 40 m 2 pond and another pond with same area was encircled with bamboo fence. Mud crab fattening in cage and in encircled earthen area were considered as Treatment-1 and Treatment-2, respectively with three replications each to compare the fattening system. Single adult non-gravid female crab (204.42 ± 2.58g) was stocked into each compartment of the cages and 80 crabs (204.42± 2.58g) were also stocked into earthen pond @ 2 indiv./ m 2 . The crabs were fed with chopped tilapia @ 8% of body weight twice daily. Survival rate of crab was found 93.75 ± 6.25% and 86.12 ± 2.16% respectively in cages and encircled earthen area. Significantly (P<0.05) higher total production of crab from cages (3.30±0.08 kg/m 2 ) was recorded than the encircled earthen area (0.37±0.01 kg/m 2 ). Comparative benefit-cost analysis showed that bamboo cage fattening attained higher net profit (Tk 91,630.00) than crab fattening in encircled earthen area (Tk 9,345.00) from 12 crops (12-16 days per crop) fattening period. The present study revealed that mud crab fattening using bamboo cage might be better than encircled earthen area with fencing in Bangladesh.

Previously, we have succeeded in converting induced pluripotent stem cells (iPSCs) into cancer stem cells (CSCs) by treating the iPSCs with conditioned medium of Lewis lung carcinoma (LLC) cells. The converted CSCs, named miPS-LLCcm cells, exhibited the self-renewal, differentiation potential, and potential to form malignant tumors with metastasis. In this study, we further characterized miPS-LLCcm cells both in vivo and in vitro. The tumors formed by subcutaneous injection showed the structures with pathophysiological features consisting of undifferentiated and malignant phenotypes generally found in adenocarcinoma. Metastasis in the lung was also observed as nodule structures. Excising from the tumors, primary cultured cells from the tumor and the nodule showed self-renewal, differentiation potential as well as tumor forming ability, which are the essential characters of CSCs. We then characterized the epigenetic regulation occurring in the CSCs. By comparing the DNA methylation level of CG rich regions, the differentially methylated regions (DMRs) were evaluated in all stages of CSCs when compared with the parental iPSCs. In DMRs, hypomethylation was found superior to hypermethylation in the miPS-LLCcm cells and its derivatives. The hypo- and hypermethylated genes were used to nominate KEGG pathways related with CSC. As a result, several categories were defined in the KEGG pathways from which most related with cancers, significant and high expression of components was PI3K-AKT signaling pathway. Simultaneously, the AKT activation was also confirmed in the CSCs. The PI3K-Akt signaling pathway should be an important pathway for the CSCs established by the treatment with conditioned medium of LLC cells.