小林 眞理子

A Japanese resident bird, Phalacrocorax carbo hanedae (Japanese name: Kawa-u), was threatened with extinction due to deterioration of its habitat in the 1970s, but the population has since recovered thanks to environmental protection measures. This study analyzed the genetic diversity of 18 Kawa-u individuals living in the basins of the Abe and Warashina rivers in Shizuoka Prefecture, Japan. We obtained seven haplotypes of mitochondrial D-loop sequences and compared them with 49 European P. carbo D-loop haplotypes. We identified four new haplotypes but no clear genetic evidence distinguishing the Kawa-u as a distinct subspecies of P. carbo. Our results suggest the need for further surveillance of the P. carbo genetic lineage, regardless of the geographical distribution.

The level of Listeria monocytogenes contamination of domestic retail meat in Tokyo, Japan, was assessed by comparison of isolates from 2004 to 2007 with those isolated before 2003. The overall prevalence of L. monocytogenes among these samples significantly diminished over time (1998-2003, 28.0%; 2004-2007, 17.6%) reflecting a significant decrease in the frequency of contamination of beef. Serotype 1/2a was isolated most frequently, reflecting a change in the predominant serotype in pork from 1/2c to 1/2a. We performed a simple genetic subtyping method based on 3 genes, iap, sigB, and actA, as well as traditional multilocus sequence typing to classify the allele types (ATs). No extensive variation among sequence types was detected. However, increased genetic diversity among the ATs of the 3 genes in the 2004-2007 isolates was evident. We identified AT 26 of the iap gene, which was not previously reported in Japanese isolates, and 6 ATs of the sigB gene, including 4 with nonsense mutations not currently registered in L. monocytogenes DNA databases. sigB is an evolutionally conserved gene that plays a role in the stress response. Our results indicate that the sigB gene may be relatively unstable among L. monocytogenes strains circulating in Japan.

We investigated changes in cortisol (COR) concentration, which is well known as an index of stress in the serum of dairy cattle. The COR concentrations in serum obtained from dairy cattle were collected during practical training of first-year students on a farm attached to the Nippon Veterinary and Life Science University. Mean COR concentration in serum determined after practical training was significantly higher (P &lt 0.001) than that in serum collected before training. Discriminant analysis was used to classify the relation between COR concentration of serum collected before and after practical training. In conclusion, the data was bipartite according to the percentage of rise (rise rate) of COR concentration. Although the percentage of the rise was more than 300% in the high-rise-rate group, there was a significant negative correlation (P &lt 0.05) between age and COR concertation. It was thought that the high-rise-rate group has a chance to decrease stress after more experience. In contrast, the low-rise-rate group included 3 cattle indicating high COR concentration before and after practical training. Those 3 cattle were thought to be stressed easily. It is suggested that there was individual difference to stress.

The food-borne pathogen Listeria monocytogenes is present persistently in food processing environments, where this bacterium is exposed to various stress factors, including oxidative stress. This study aimed to elucidate the temperature-dependent response of L. monocytogenes to H2O2 exposure and the phenotypic changes in colony formation by H2O2-treated bacteria. Survival curves indicated an increase in the resistance to H2O2 in L. monocytogenes as the temperature decreased during the stress exposure procedure. Transcriptional induction of genes with key roles in response to H2O2, including sigB and kat, was observed at 37 degrees C, but not at 20 degrees C, whereas other stress response genes were induced at both temperatures. Following H2O2 exposure, L. monocytogenes produced small colony phenotypes and the colony size decreased in a stress exposure duration-dependent manner. Resuscitated cells with no ability to form colonies in the absence of sodium pyruvate were also found. Our findings show the possibility that a sequential transition in the injury phenotype from small colony phenotype to resuscitated cells occurred during the course of exposure to H2O2. The higher H2O2 resistance at 20 degrees C than 37 degrees C suggests further investigation of the response to H2O2 exposure under the lower temperatures, including refrigeration temperature, which may contribute to elucidation of bacterial survival over extended time periods in food-processing environments.

<p>配合飼料原料として使用される油粕は，古くからサルモネラ汚染が報告されている．油粕の製造現場では，製品や製造環境材料を対象に，定期的にサルモネラ検査を実施しているが，製造現場に適した検査法として，近年，QUALIBAX^TMシステムなどの簡易迅速検査法が開発されてきた．しかしながら製造現場では，工程汚染の早期発見や製品の迅速な出荷などを目的に，さらなる迅速化が求められている．そこで，製造環境材料などからサルモネラを短時間で効率よく検出することを目的に，検査時間のさらなる短縮を試みた．まず，前増菌培地を検討した結果，MP培地はBPWなどの他の培地と比較し，7 hr培養後の菌数は有意に高かった（p<0.001）．次に，前増菌培養後のDNA抽出段階においてQuickGene-Mini80を用いることにより，感度が大幅に向上した．MP培地，QuickGene-Mini80およびQUALIBAX^TMシステムを組み合わせて使用することにより，10 hr以内でサルモネラを検出できる可能性が示唆された．この方法は製造現場における品質管理に有用であると考えられた．</p>

Pulse field gel electrophoresis (PFGE) is widely used for listeriosis surveillance. Although this technique is effective for epidemiology, the data among laboratories are inconsistent. We previously reported a method for Listeria monocytogenes subtyping combined with sequence analysis of partial iap and whole genome restriction fragment length polymorphism (RFLP) using XbaI, ClaI (BanIII) and PstI. However, distinguishing subtypes was challenging, because the output comprised complicated fragment patterns. In this study, we aimed to establish a simple genotyping method that does not depend on visual observation, rather it focuses on multi-locus sequence typing (MLST) using three genes, iap, sigB and actA. Sixty-eight strains of L. monocytogenes including EGD-e as a reference strain were investigated to ensure consistency with previous data on the genetic characterization. All strains were grouped into 29 types by both analyses. Although there are some differences in classification, major clades included the same strains. Simpson's indices of diversity (SID) by MLST and iap-RFLP-based typing were 0.967 (95% confidence interval [CI]: 0.955/0.978) and 0.967 (95% CI: 0.955/0.979), respectively. The discriminatory power of both methods can be considered almost identical. Compared with the results of 38 selected strains, the strains within the MLST clusters in this study coincided with those obtained using PFGE. Thus, the MLST strategy could help differentiate among L. monocytogenes isolates during epidemiological studies.

In this study, we investigated the effect of aging on biochemical markers in serum obtained from Thoroughbred horses (n = 30) and ponies (n = 15). Aging was observed to have an effect on albumin, total bilirubin, thyroxine, and iron levels. The triglyceride concentration in ponies was found to be significantly higher than in Thoroughbreds. Furthermore, an age-related increase in triglycerides was only observed in ponies. There was no aging effect on diacron-reactive oxygen metabolites and biological antioxidant potential concentration. A significant negative correlation between age and bilirubin, known as a strong antioxidative substance, was obtained in both the Thoroughbred and pony groups. However, the distribution area of data was different due to higher bilirubin concentrations in Thoroughbreds. The serum iron levels were correlated with serum triglyceride levels in ponies. We propose that the metabolism of ponies differs from that of Thoroughbreds and that careful breeding and appropriate exercise are required for aging ponies. (C) 2016 Elsevier Inc. All rights reserved.

In this study, iodine and thyroxin (T4) concentrations in the serum of 69 horses were investigated. Higher iodine concentrations were obtained from the horses housed in Chiba Prefecture. In contrast, T4 concentrations of horses at Shizuoka Prefecture were higher than those of horses at Chiba Prefecture. There was a significant correlation (r = 0.643, P &lt; 0.001) between the iodine and T4 concentrations of horses at Saitama and. Shizuoka prefectures. Although a significant correlation (r=0.794, P &lt; 0.001) was also observed in the investigation of all horses at Chiba Prefecture, the distribution area of the data was separated from the data of horses housed in Saitama and Shizuoka prefectures. A higher iodine concentration in the environment is expected in the sampling area at Chiba Prefecture. Thus, it was suggested that the concentrations of iodine in the serum of horses are influenced by geological differences. It was thought that equine senim is a useful sample for monitoring.

Lead (Pb) is known to be highly poisonous, and the acute poisoning of Cd causes the abdominal pains, vomiting, and shock. The digestive and nervous symptom is observed in the chronic lead poisoning. It was also known that the defect in hemoglobin synthesis by Pb produce anemia. The release of Pb into the environment presents a source of exposure for wild animals. In this study, we examined the utility of a new Pb-monitoring index in mice administered Pb. A solution containing 0.02, 0.2, 2, or 4 ppm lead chloride (PbCl2) was administered intraperitoneally to mice, and the Pb contents of the kidney and liver were determined at designated time points. The mean Pb content of both organs increased depending on the administered Pb dosage. Although the results of control was near the detection limits, the administration of 4 ppm in 4 weeks resulted in Pb levels of 260 mg ppm/wet weight and 110 ppm wet weight in the kidney and liver, respectively. However, there were no significant relationships among administered dose, duration of Pb treatment, and liver or kidney Pb content. Then, values in all mice administered control or 0.02 mg Pb were located inside the ellipse, representing the confidence area of the new index, and values in all mice administered more than 2 mg Pb were located outside the ellipse. These results confirm that animals exposed to high concentrations of Pb would be detected by this new index.

G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is associated with various physiological functions. It is reported that the genetic variant of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation functionally relates to obesity in humans. Obesity is a common nutritional disorder also in dogs, but the genetic factors have not ever been identified in dogs. In this study, we investigated the molecular structure of canine GPR120 and searched for candidate genetic variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those of other species, and seven transmembrane domains and two N-glycosylation sites were conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus, hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs, resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant c.595C&gt;A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly higher in dogs with higher body condition scores, i.e. 0.320 in BCS4-5 dogs, 0.175 in BCS3 dogs and 0.000 in BCS2 dogs. We conclude that c.595C&gt;A (p.Pro199Thr) is a candidate variant relating to obesity, which may be helpful for nutritional management of dogs.

A food-borne pathogen, Listeria monocytogenes serotype 4b, has been frequently isolated from patients with listeriosis, and numerous outbreaks of listeriosis are associated with this serotype. In the present study, we performed subtyping of L. monocytogenes serotype 4b strains on the basis of genetic analyses. Thirty-four isolates of serotype 4b were classified into 8 genotypes, namely genotypes 12, 15, 16, 17, 18, 23, 24, and 25, on the basis of the sequence for the partial iap gene. Genetic analyses revealed that genotype 16 and genotypes 24 and 25 belong to epidemic clone I (ECI) and ECII, respectively, which have been frequently associated with listeriosis outbreaks in the United States and Europe. The genotype isolated most frequently from retail meats in the Tokyo metropolitan area was genotype 12 (52%), followed by genotype 16 (29%), which belongs to ECI. We suggest that ECI is a common subtype of L. monocytogenes in retail meat in the area under investigation. On the other hand, ECII isolates were confirmed to be present in retail meat in Japan but were rare.

To understand the effects of silicon (Si) in the urine with respect to the formation of urinary stones, the distribution of Si in urine was observed. Urine samples from cats with urolithiasis (n=10) and healthy cats (n=15) were used. The concentration of Si in the cats with urolithiasis was significantly higher (P&lt;0.001). A significant correlation (P&lt;0.05) was observed between the concentration of Si and those of other elements, such as calcium, magnesium, phosphorus, potassium and iron, only in the urine of the healthy cats. The distribution of elements in the urine differed between the cats with urolithiasis and the healthy cats. The Si concentration and its relationship with other elements were suggested to be useful biomarkers for urolithiasis in cats.

Some Listeria monocyto genes strains, termed persistent strains, originate from the same processing plant and have the ability to survive and grow over extended periods of time at contamination sources. In order to evaluate biofilm formation by such persistent strains, we isolated the pathogen from chicken samples collected from the same retail shop in repeated visits over 6 months. Strains that were of serotype 1/2b and were assigned to the same genotype by multi-virulence-locus sequence typing analysis were isolated on repeated occasions from December 1997 to June 1998 and thus were defined as persistent strains. In the present study, biofilm formation by the persistent strains was evaluated using microplates at 30 and 37 degrees C. The biofilm-forming capability was measured after cells attaching to the microplate well were stained with crystal violet. Comparison of biofilm formation at 30 degrees C among the persistent strains showed that a significantly higher amount of the stain was obtained from the persistent strains isolated from December to March than from those isolated from April to June. However, no significant difference in biofilm formation at 30 degrees C was observed between persistent and nonpersistent groups of L. monocyto genes strains. In contrast, biofilm formation at 37 degrees C was consistent among the persistent strains, and they produced significantly more biofilm at 37 degrees C than did the nonpersistent strains. The persistent strains were also found to change their biofilm-forming ability in a temperature-dependent manner, which may suggest that the persistent strains alter their biofilm formation in response to changing environmental factors.

Twenty nine oil-soaked birds were collected from around the Coast of Tsushima Island. The contents of eight elements in the livers and kidneys of the birds were investigated. Statistically higher concentrations of vanadium and thallium in the liver and of titanium in the kidney were found in the birds that were found dead compared with those that died after rescued. A significant correlation (r=0.695, P&lt;0.01) was observed only for the molybdenum content between the kidneys and livers from the birds found dead. Although the controls of the eight elements of birds investigated in the present study remain unexplained, some of lower concentration in rescued birds can be blamed on a decrease in food intake of birds. The relation between oil contamination and concentration of elements need to be further explored.

Titanium (Ti) is used in many fields, while cadmium (Cd) is known to cause the itai-itai disease. In the present study, possible interactions between titanium and cadmium were investigated. Aorta, taenia coli, and liver were removed from male guinea pigs. Muscle tension was measured using intact aorta and taenia coli and using beta-escin-permeabilized taenia coli in a physiological salt solution and a hyperpotassium solution containing Cd and/or Ti. Cellular Cd contents were determined using all tissues after washout with EDTA solution. Cadmium-induced relaxation in the hyperpotassium solution recovered significantly (P &lt; 0.01) following Ti treatment in taenia coli, but not in the aorta. In beta-escin-permeabilized taenia coli, the percentage recoveries after Cd treatment and after Ti plus Cd treatment were 67.3 +/- 8.7 % (n = 4) and 87.7 +/- 3.8 % (n = 4), respectively, compared with Ca-induced control contraction. Cellular Cd contents in taenia coli decreased significantly following treatment with Ti 10(-4) M. Although similar results were obtained using the aorta and the liver, there were no significant differences between the control and Ti 10(-5) M. High concentrations of Ti may reduce cellular Cd content.

The establishment of a classification system for domestic animals on consumed feed stuff is thought to be important from both a hygiene and market point of view. We collected plasma samples of Romney lambs (Ovis aries) which were fed one of the following: a herb-clover mix (n=10) which included chicory, red clover, white clover and plantain; a plant-grass mix (n=10) which included plantain, ryegrass and white clover; or a grass mix (n=10) which included ryegrass and white clover. A total of 20 elements in plasma samples obtained from the lambs were analyzed using inductively coupled plasma mass spectrometry. The data were then analyzed by principal component analysis. The lambs were divided into three groups on a score plot depending on the different feed conditions. Furthermore, discriminant analyses of the elements were examined, using linear discriminant analysis with forward stepwise regression. This discriminant function correctly classified the samples from each group. The accuracy of classification of each group, as shown by 10-fold cross-validation, proved the effectiveness of the established discriminant function. It is concluded that using linear discriminant analysis might be a useful tool for the validation of elements from plasma in lambs grown in different conditions.

The cadmium (Cd) contents in hair of macaques (n = 45, Macaca fuscata) living on the Shimokita Peninsula were investigated. The mean Cd contents in the hair of Japanese (n = 34, 5.01 mu g/g) and macaques (3.05 mu g/g) tendency to be higher than those of animals living other areas. The Cd contents of hair of wild macaques were significantly (p &lt; 0.01) lower than that of humans, although three were no significant difference between Cd contents of humans and that of the macaque in captivity. The hair of the macaque was suggested as a useful sample for measurement of Cd contamination in the environment.

The drinking facilities in some public spaces (such as parks, public baths, etc.) in Japan which many unspecified people often use are useful for taking moisture easily and rapidly. Sometimes it might be also accepted that it is good for the prevention of diseases and for the health. The cleaning of these facilities is sure to be done in regular. However, they have misgivings about dirt in more short time by using of many people. It would be necessary for the public health to research the safety of them. In the present study, the pollution of inorganic components, inorganic anions, general bacteria and total coliforms in the initial getting water to stay near by the faucets, on the knobs and the intakes were examined.

For human safety, we investigated how metals (aluminum, cadmium, chromium, copper, lead, manganese and tin) are leaked from fused slags by contact with acid rain and basic concrete effluent. We obtained 13 fused slags prepared from general garbage. Elution tests (6 hours interval in the room temperature) by using diluted nitric acid (instead of acid rain), water, and diluted potassium hydroxide (instead of basic concrete effluent) were performed. As a result, it has been understood that the elution rates are greatly different according to both the kinds of metal and slag. The influence of aluminum was especially large. The elution concentrations of aluminum from the slags were ppm-level in alkaline. On the other metals, the elution concentrations were lower than that of aluminum. The elution pattern also differed from aluminum, and it seemed to influence the character of the metals (dissolubility in alkaline and ability to be an oxyanion).

The concentrations of elements in urine obtained from cats with urolithiasis were compared with those of healthy cats. The concentration of several elements, such as sodium (Na), phosphorus (P), sulfur (S), and potassium (K), in urine obtained from cats with urolithiasis was significantly higher than that of healthy cats. A significant correlation (p &lt; 0.01) was found between the concentration of magnesium (Mg) and that of other elements, such as P (r = 0.8913), S (r = 0.6817), and K (r = 0.8391), in the urine obtained from healthy cats. A significant correlation (r = 0.7422, p &lt; 0.05) was also obtained between the concentration of K and that of P in urine collected from cats with urolithiasis, but the slope of regression line was significantly different from that of the urine obtained from healthy cats. Other correlations observed in healthy cats were not obtained from cats with urolithiasis. However, a significant correlation between the concentration of magnesium (Mg) and that of calcium was obtained only from cats with urolithiasis. The results of the present study suggest that urinary concentrations of various elements in cats with urolithiasis are higher than those of healthy cats. Furthermore, the balance of elements in the urine of cats with urolithiasis was altered.

A high concentration of vanadium (V) has toxic effects on human and animals and is one of environmental pollutants. In the present study, we have conducted a fundamental study using cultured Vero cells from monkey kidney for the future environmental monitoring. Orthovanadate (VAN), one of V compounds, of 10(-10) and 10(-8) M did not affect the cell growth although the higher concentration of above 10(-6) M VAN inhibited the cell growth accompanied with the decrease in cell numbers and morphological changes. Given that the washing method with ice-cold Li is also effective for determination of the cellular Na content, we used this method for the determination of the V content of the Vero cells. The V distributions in Vero cell; in the 10(-3) M VAN solution, extracellular and intracellular were obtained as 1:0.564:0.036 and 1:0.662:0.098 at 60 and 120 min after the treatment of VAN. The intracellular V content was 10% of the applied concentration of VAN. Consequently, it was suggested that V concentration of 10(-7) and 10(-6) M in the tissue and environment, respectively, might become the threshold concentration; a criterion of the environmental contamination when we carry out environmental monitoring.

The cadmium (Cd) content in the kidneys and livers of wild birds was compared after classification based on the type of migration and the breeding area. A high Cd content was detected in the organs of Pacific loons breeding in North America, but these birds were thought to have been affected by oil contamination. The Cd content of organs from spotbill ducks, which are birds that are resident in Japan, tended to be higher than those of other birds that breed outside Japan. The rank order of the mean Cd level with respect to location was "only in Eurasia" < "both Eurasia and North America" < "only in North America". The type of migration did not affect the Cd content of the organs. We also investigated the relationship between the Cd content of the organs and the Japanese environmental concentration of Cd. The Cd contents of organs from birds collected on the shore of the Japan Sea were generally higher than those of the birds collected near the Pacific Ocean. These results seem to be related to the concentration of Cd in the soil. From these results, we showed that the differences in the Cd content in organs from Japanese wild birds were related to their breeding area but not to the type of migration. Further, the area from which the wild birds were collected was strongly related to the Cd content of the organs. This demonstrated the relationship between the environmental and soil conditions in Japan and the level of pollution of the birds studied. © 2011 Nova Science Publishers, Inc.

This study was conducted to decent-line the prevalence of Listen monocytogenes in retailed meats, comprising beef. chicken, and pork. in the Tokyo metropolitan area. A total of 379 samples of retailed meat were collected from 1998 to 2003, most of which were obtained by simultaneously purchasing the three classes of meat from a shop and then making another simultaneous purchase of meat from the same shop a few weeks later The prevalence of L monocytogenes was 28.0%, and the serotypes isolated were mainly 1/2a, 1/2b, 1/2c. and 4b Comparison of the prevalence of each scrotype among the classes of meat showed a predominant distribution of serotypes 1/2a. 1/2b, and 4b in chicken, while serotype 1/2c was dominant in pork. A total of nine cases considered to be due to persistence and/or cross-contamination were found Most of the strains involved in persistence and/or cioss-contamination were of serotypes 1/2c or 4b These results suggest that contamination in retailed meat in Japan is at almost the same level as in other countries and that chicken has the highest potential as a source of contamination and infection In addition, we suggest that the ecological niche of serotype 1/2c is distinct from those of 1/2a. 1/2b. and 4b. which may explain why human hosts have less opportunity to be exposed to serotype 1/2c and why there is a lower rate of isolation of this serotype from cases of human listeriosis.

© 2010 by Nova Science Publishers, Inc. All rights reserved. The cadmium (Cd) content in the kidneys and livers of wild birds was compared after classification based on the type of migration and the breeding area. A high Cd content was detected in the organs of Pacific loons breeding in North America, but these birds were thought to have been affected by oil contamination. The Cd content of organs from spotbill ducks, which are birds that are resident in Japan, tended to be higher than those of other birds that breed outside Japan. The rank order of the mean Cd level with respect to location was "only in Eurasia" < "both Eurasia and North America" < "only in North America". The type of migration did not affect the Cd content of the organs. We also investigated the relationship between the Cd content of the organs and the Japanese environmental concentration of Cd. The Cd contents of organs from birds collected on the shore of the Japan Sea were generally higher than those of the birds collected near the Pacific Ocean. These results seem to be related to the concentration of Cd in the soil. From these results, we showed that the differences in the Cd content in organs from Japanese wild birds were related to their breeding area but not to the type of migration. Further, the area from which the wild birds were collected was strongly related to the Cd content of the organs. This demonstrated the relationship between the environmental and soil conditions in Japan and the level of pollution of the birds studied.

With a view to investigate whether in-ovo cadmium (Cd) exposure can attribute toxic effects in developing avian embryo, the fertile eggs of Japanese quail were injected with Cd and the mortality during incubation and the body weights of day-old hatchlings were measured. The Cd toxicity in the embryo were also assessed by evaluating some well-known oxidative stress markers such as metallothionein (MT) mRNA expression, catalase activity and malondialdehyde (MDA) production in day-10 male and female embryos exposed to Cd with or without ascorbic acid. Results showed that as minimum as 1 mu g/egg of in-ovo Cd administration increased the embryonic death and decreased the hatchling body weights. A slightly higher mortality rate was found in the 1 mu g Cd/egg received male embryos than in the female embryos. Compare to the control, higher MT mRNA expression and MDA generation were observed in 1 mu g Cd/egg received live embryos irrespective of sex. Co-exposure of 50 mu g ascorbic acid with 1 mu g Cd/egg inhibited the increse in MDA production in embryos of both sexes but the augment of MT mRNA expression was supressed only in female embryos. These results suggested that in-ovo Cd pollution in avian species might cause the embryonic toxicity leading to death, and the sensitivity of developing quail embryo to antioxidant protection against Cd toxicity is not exactly similar in both sexes of embryos.

Data obtained from wildlife are useful for the evaluation of risks to human health, including those to the next generation. In this study, various environmental pollutants were investigated using samples from wildlife. We have previously investigated the degree of contamination with toxic elements, such as cadmium (Cd), chromium (Cr), molybdenum (Mo), thallium (Tl) and vanadium (V), in kidney and liver samples obtained from wild birds (Mochizuki et al., 1998, Mochizuki et al., 1999, Mochizuki et al., 2002 a, b, Mochizuki et al., 2005, Ueda et al., 1998). Studies that use wildlife are prone to problems (Krimsky, 2000), although the importance of biological monitoring has been pointed out in many studies that have investigated environmental pollution (Colborn et al.,1996). It is known that the levels of several elements, such as Cd, nickel (Ni) and selenium (Se), increase and decrease depending on the age of the animal (Elinder et al.,1981), and detailed analysis of the age of wildlife specimens is usually difficult. Another problem is that it is difficult to draw inferences from the degree of pollution of the habitat of wildlife such as migratory birds.Carnivores are frequently used for studies involving wildlife because they are positioned at the top of the food chain. The greater scaup (Aythya marila) is generally classified as a carnivorous bird that eats animals such as shellfish. However, it is known that this bird also uses feed of vegetable origin, depending on the environments in which it rests during migration. The often narrow classification of feeding habits is a daunting problem for studies of wildlife. To obtain a detailed understanding of the actual migratory flight path and the degree of contamination of the environment inhabited by migratory species is even more difficult. Thus, the data obtained from wildlife are usually distributed over a wide range, and outliers are often obtained. We investigated these problems using the data obtained in our studies of wildlife, and suggest the possibility of a new index for biological monitoring. © 2009 Nova Science Publishers, Inc.

The authors have recently developed a new cadmium (Cd) index (Cd standard regression line; CSRL) based on data from uncontaminated samples from many species. However, the samples from wildlife organs are often, and sometimes, we can not remove the blood in the tissues. The Cd remained in the blood may affect the content of the organ. Thus, preliminary work for an epidemiological study was performed upon a laboratory animal, the rat. After establishment of a constant level of Cd in rat serum, the Cd contents of various organs were compared following perfusion with 0.8% NaCl, with 1mM EDTA, or without any treatment. No significant differences were found among these organs, and the Cd levels in the organs were dependent on the infused Cd concentration. These results suggest that the Cd content in the blood did not affect the evaluation of the Cd content of the organs investigated. After the infusion of Cd, The ratio of liver and renal cortex was separated from the slope of the CSRL and was located at the upper part of the CSRL, while the data for the liver and renal medulla were located on the CSRL. From the results, we assumed that the assessment was correct, even if the content in the kidney cortex was considered to represent the Cd content of the whole kidney, when we could obtain the data only from the cortex. Furthermore, significant correlations were observed among the other organs, and strong multiple correlation was obtained among the Cd contents in liver, renal cortex, adrenal, renal medulla, pancreas, spleen and testis. These results suggest that contamination can be evaluated by measurement of the Cd content in these organs, even if samples of liver and/or kidney cannot be obtained.

Phylogenetic analyses were carried out on a total of 118 Listeria monocytogenes isolates from foods or food processing environments, and 7 isolates from listeriosis patients in Japan to evaluate the genetic variation in the pathogen in this country. Isolates of serotypes 1/2a, 1/2b and 4b were mainly examined to assess the risk of exposure of humans to L. monocytogenes from foods in Japan. The nucleotide sequences of the part of the iap gene that contains the region encoding the threonine-asparagine repeat units were determined in order to construct phylogenetic trees of the isolates investigated. A phylogram showed high genetic diversity among lineage 2 isolates. while the lineage I isolates showed clonal characteristics. The results of the genetic analyses suggested the presence of rare putative lineage 3 isolates and epidemic clone I (ECI) isolates in foods in Japan. The results showed that ECI was also isolated from listeriosis patients. The genetic variation in L. monocytogenes in Japan reported here suggests the necessity of monitoring the pathogen in foods and environments in addition to surveillance of listeriosis patients. (C) 2008 Elsevier B.V. All rights reserved.

The degree of cadmium (Cd) contamination in wildlife is often used as an indicator in the environmental monitoring of Cd poisoning. However, previous studies have not clarified the correlation between levels in wildlife and levels in the environment by comparing levels among different species of animals; therefore, assessing the level of pollution in this manner is not considered a reliably accurate indicator of levels in the environment. The aim of this study was to establish a new indicator for the non-polluted warm-blooded animals, one that is not species-dependent, which will facilitate using different species for Cd monitoring. First, the previous publications regarding Cd contents in wildlife, 27 reports in which Cd contents were represented as arithmetic means and described for both kidney and liver were selected. A regression line (CSRL) between Cd contents of kidney and that of liver was obtained in a high correlation coefficient (R-2 = 0.943, P &lt; 0.01). The mean values from land and waterfowl, terrestrial mammals, seabirds, marine mammals, and non-polluted humans were located on the line and aligned in order. CSRL might allow an accurate determination of whether an animal is polluted by Cd. CSRL was confirmed using well-established and widely recognized pollution models such as Itai-itai patients and Cd-exposed experimental animals. The Cd contents from these models were located in different positions relative to CSRL depending on the level of contamination. Thus, this new indicator determining the Cd-pollution status of animals would be useful for environmental monitoring.

To explore the possible endocrine-disrupting effect of cadmium (Cd), we have tested its role on very-low-density apolipoprotein II mRNA (apoVLDL II) expression by diethylstilbestrol (DES) in Japanese quail. Three-week-old immature male quail were intraperitoneally injected with DES (10mg/kg body wt and 24hrs before sacrifice) to induce apoVLDL II mRNA in the liver. The same birds were intraperitoneally injected with 0.001, 0.01, 0.1, 1 or 3 mg/kg body wt of CdCl2 at 48 hrs before DES injection. A reverse-transcription polymerase chain reaction (RT-PCR) was applied to quantify the mRNA level. We found that 0.1 mg/kg body wt of Cd injection contributed an additive effect in DES-stimulated apoVLDL II mRNA expression, whereas Cd injection above this level suppressed the effect. The present results suggest that Cd has biphasic effects on estrogen-dependent gene transcription, and 0.1 mg/kg body wt of Cd administration can mimic the estrogen functions in Japanese quail.

The invasion ability of Listeria monocytogenes into cultured cells has been used to evaluate its pathogenicity. In this study, invasive ability was investigated using Vero and Caco-2 cell lines. The form of invasion showed no morphological differences between both cell lines inoculated with L. monocytogenes L89-H2 or L96-23C1 strains when double fluorescence stained with rhodamine and FITC or with Giemsa staining. Recovery count and recovery rate of L. monocytogenes from Vero cells was related to the number of inoculated bacteria (2 x 10(5) to 2 X 10(7)/ml) in a bell-shape pattern, though the relationship was unclear in Caco-2 cells. Recovery rate of L. monocytogenes was higher in Vero cells than Caco-2 cells at a multiplicity of infection (MOI) 10, though the rates in both cells showed different stable stages over a considerably wide range of MOI. The recovery rate of all five L. monocytogenes strains from listeriosis patients was 15% at MOI 10 from infected Vero cells, while meat-derived strains showed variable rates regardless of the serovar. These results suggest that the Vero cell line is suitable for an invasion assay and that a recovery rate of 15% may be the critical limit for the expression of pathogenicity in the host. (c) 2005 Elsevier B.V. All rights reserved.

In this study, we examined the inhibitory mechanism of monensin on high K+-induced contraction in guinea-pig urinary bladder. The relaxant effect of monensin (0.001-10 mu M) was more potent than those of NaCN (100 mu M-1 mM) and forskolin (3-10 mu M). Monensin (0.1 mu M), NaCN (300 mu M), or forskolin (10 mu M) inhibited high K-induced contraction without decreasing [Ca2+](i) level. Monensin and NaCN remarkably decreased creatine phosphate and ATP contents. Monensin and NaCN inhibited high K-induced increases in flavoprotein fluorescence, which is involved in mitochondrial respiration. Forskolin increased cAMP content but monensin did not. Monensin increased Na+ content at 10 mu M but not at 0.1 mu M that induced maximum relaxation. In the alpha-toxin-permeabilized muscle, forskolin significantly inhibited the Ca2+-induced contraction, but monensin did not affect it. These results suggest that the relaxation mechanism of monensin in smooth muscle of urinary bladder may be an inhibition of oxidative metabolism.

Discrimination was attempted on 14 Listeria monocytogenes strains isolated from commercially available Japanese pork and chicken. Examination of the isolates was performed by restriction fragment length polymorphism (RFLP) analysis of the chromosomal DNA and amplified products and comparison of the nucleotide sequences of the amplified products. A polymorphism region containing the repeated sequences in the iap gene was amplified by the polymerase chain reaction (PCR). The genetic analyses could discriminate the 14 isolates in combination with traditional serotyping, and some strains isolated from different meats were confirmed to have a genetically close relationship. Genetic analyses used in the present study would be useful for the elucidation of the pathogen tracks from contaminated sources to humans and of the ecological niche in the food environment. (C) 2005 Elsevier B.V. All rights reserved.

Foodborne disease by Listeria monocytogenes, serovar 1/2a has recently been reported in many countries. Although contamination by this bacteria is also known to be gradually spreading among the marketed foods of Japan, there is little information on relation between listeriosis and food contamination. In the present study, the characteristics of the genomic structures of serovar 1/2a were compared among the isolates from marketed meats and listeriosis patients. Several isolates from meats purchased at the same shop on different days had the same genomic structure, and prolonged contamination was suggested by the conditions in the shop. Genomic structures of one strain isolated from meat were identical to those of two isolates from a patient. Another isolate was obtained from meats purchased at two different shops, and this isolate was also identical to that of the isolates from another patient. These findings suggest that the isolates from meat may have caused the listeriosis in the patients, and that the strains may have somehow traveled between the shops.