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1

In Vivo Effects of Bisphenol A in Laboratory Rodent Studies  

PubMed Central

Concern is mounting regarding the human health and environmental effects of bisphenol A (BPA), a high-production-volume chemical used in synthesis of plastics. We have reviewed the growing literature on effects of low doses of BPA, below 50 mg/kg/day, in laboratory exposures with mammalian model organisms. Many, but not all, effects of BPA are similar to effects seen in response to the model estrogens diethylstilbestrol and ethinylestradiol. For most effects, the potency of BPA is approximately 10 to 1,000-fold less than that of diethylstilbestrol or ethinylestradiol. Based on our review of the literature, a consensus was reached regarding our level of confidence that particular outcomes occur in response to low-dose BPA exposure. We are confident that adult exposure to BPA affects the male reproductive tract, and that long-lasting, organizational effects in response to developmental exposure to BPA occur in the brain, the male reproductive system, and metabolic processes. We consider it likely, but requiring further confirmation, that adult exposure to BPA affects the brain, the female reproductive system, and the immune system, and that developmental effects occur in the female reproductive system. PMID:17683900

Richter, Catherine A.; Birnbaum, Linda S.; Farabollini, Francesca; Newbold, Retha R.; Rubin, Beverly S.; Talsness, Chris E.; Vandenbergh, John G.; Walser-Kuntz, Debby R.; vom Saal, Frederick S.

2007-01-01

2

Auditing laboratory rodent biosecurity programs.  

PubMed

A rodent biosecurity program that includes periodic evaluation of procedures used in an institution's vivarium can be used to ensure that best practices are in place to prevent a microbial pathogen outbreak. As a result of an ongoing comprehensive biosecurity review within their North American and European production facilities, the authors developed a novel biosecurity auditing process and worksheet that could be useful in other animal care and use operations. The authors encourage other institutions to consider initiating similar audits of their biosecurity programs to protect the health of their laboratory animals. PMID:24150170

Porter, William P; Horn, Mandy J; Cooper, Dale M; Klein, Hilton J

2013-10-22

3

Susceptibility of laboratory rodents to Trichinella papuae.  

PubMed

Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of 241.5±41.0 for T. papuae, 432.6±48 for T. pseudospiralis, and 528.6±20.6 for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp. PMID:24516265

Sadaow, Lakkhana; Intapan, Pewpan M; Boonmars, Thidarut; Morakote, Nimit; Maleewong, Wanchai

2013-12-01

4

Analysis of Behavior in Laboratory Rodents  

Microsoft Academic Search

The nervous system is designed to produce behavior, and so behavioral analysis is the ultimate assay of neural function. In this chapter we provide an overview of the behavior of rodents. We also provide references for testing details. Most of the behavioral meth- odology comes from research on rats, but the ethograms of rodents are similar enough to allow for

Ian Q. Whishaw; Forrest Haun; Bryan Kolb

5

Estimation of Wildlife Hazard Levels Using Interspecies Correlation Models and Standard Laboratory Rodent Toxicity Data  

Microsoft Academic Search

Toxicity data from laboratory rodents are widely available and frequently used in human health assessments as animal model data. This study explores the possibility of using single rodent acute toxicity values to predict chemical toxicity to a diversity of wildlife species and estimate hazard levels from modeled species sensitivity distributions (SSD). Interspecies correlation estimation (ICE) models predict toxicity values for

Jill A. Awkerman; Sandy Raimondo; Mace G. Barron

2009-01-01

6

Neurogenetics of Aggressive Behavior – Studies in Rodents  

PubMed Central

Aggressive behavior is observed in many animal species, such as insects, fish, lizards, frogs, and most mammals including humans. This wide range of conservation underscores the importance of aggressive behavior in the animals’ survival and fitness, and the likely heritability of this behavior. Although typical patterns of aggressive behavior differ between species, there are several concordances in the neurobiology of aggression among rodents, primates, and humans. Studies with rodent models may eventually help us to understand the neurogenetic architecture of aggression in humans. However, it is important to recognize the difference between the ecological and ethological significance of aggressive behavior (species-typical aggression) and maladaptive violence (escalated aggression) when applying the findings of aggression research using animal models to human or veterinary medicine. Well-studied rodent models for aggressive behavior in the laboratory setting include the mouse (Mus musculus), rat (Rattus norvegicus), hamster (Mesocricetus auratus), and prairie vole (Microtus ochrogaster). The neural circuits of rodent aggression have been gradually elucidated by several techniques e.g. immunohistochemistry of immediate-early gene (c-Fos) expression, intracranial drug microinjection, in vivo microdialysis, and optogenetics techniques. Also, evidence accumulated from the analysis of gene-knockout mice shows the involvement of several genes in aggression. Here we review the brain circuits that have been implicated in aggression, such as the hypothalamus, prefrontal cortex (PFC), dorsal raphe nucleus (DRN), nucleus accumbens (NAc), and olfactory system. We then discuss the roles of glutamate and ?-aminobutyric acid (GABA), major inhibitory and excitatory amino acids in the brain, as well as their receptors, in controlling aggressive behavior, focusing mainly on recent findings. At the end of this chapter, we discuss how genes can be identified that underlie individual differences in aggression, using the so-called forward genetics approach. PMID:24318936

Takahashi, Aki; Miczek, Klaus A.

2014-01-01

7

Neurogenetics of aggressive behavior: studies in rodents.  

PubMed

Aggressive behavior is observed in many animal species, such as insects, fish, lizards, frogs, and most mammals including humans. This wide range of conservation underscores the importance of aggressive behavior in the animals' survival and fitness, and the likely heritability of this behavior. Although typical patterns of aggressive behavior differ between species, there are several concordances in the neurobiology of aggression among rodents, primates, and humans. Studies with rodent models may eventually help us to understand the neurogenetic architecture of aggression in humans. However, it is important to recognize the difference between the ecological and ethological significance of aggressive behavior (species-typical aggression) and maladaptive violence (escalated aggression) when applying the findings of aggression research using animal models to human or veterinary medicine. Well-studied rodent models for aggressive behavior in the laboratory setting include the mouse (Mus musculus), rat (Rattus norvegicus), hamster (Mesocricetus auratus), and prairie vole (Microtus ochrogaster). The neural circuits of rodent aggression have been gradually elucidated by several techniques, e.g., immunohistochemistry of immediate-early gene (c-Fos) expression, intracranial drug microinjection, in vivo microdialysis, and optogenetics techniques. Also, evidence accumulated from the analysis of gene-knockout mice shows the involvement of several genes in aggression. Here, we review the brain circuits that have been implicated in aggression, such as the hypothalamus, prefrontal cortex (PFC), dorsal raphe nucleus (DRN), nucleus accumbens (NAc), and olfactory system. We then discuss the roles of glutamate and ?-aminobutyric acid (GABA), excitatory and inhibitory amino acids in the brain, as well as their receptors, in controlling aggressive behavior, focusing mainly on recent findings. At the end of this chapter, we discuss how genes can be identified that underlie individual differences in aggression, using the so-called forward genetics approach. PMID:24318936

Takahashi, Aki; Miczek, Klaus A

2014-01-01

8

PERFLUOROOCTANE SULFONATE (PFOS) DISRUPTS THE THYROID STATUS IN LABORATORY RODENTS  

EPA Science Inventory

PERFLUOROOCTANE SULFONATE (PFOS) DISRUPTS THE THYROID STATUS IN LABORATORY RODENTS. C. Lau, J.R. Thibodeaux, R.G. Hanson, B.E. Gray and J.M. Rogers. Reprod. Tox. Div. NHEERL, US EPA, Research Triangle Park, NC. PFOS is an environmental contaminant ubiquitously found in h...

9

Breeding of wild-caught rodent cricetidae Holochilus brasiliensis under laboratory conditions.  

PubMed

The breeding of wild-caught rodent Holochilus brasiliensis (Desmarest, 1819) was studied under laboratory conditions. The mean gestation length was 28.4 days. Litter size ranged from one to five. Males matured at 2-3 months and females at 2-4.5 months of age. The oestrous cycle lasted 6-8 days. Eleven pairs observed over 6-13 months increased to a population of 276 individuals (153 males and 123 females). PMID:3540447

Mello, D A

1986-07-01

10

Diffusion MRI of Rodent Glioma at 21T National High Magnetic Field Laboratory  

E-print Network

Diffusion MRI of Rodent Glioma at 21T National High Magnetic Field Laboratory NMR Spectroscopy to understand and further develop surrogate MRI biomarkers of tumor therapy. Diffusion map of rat glioma before of therapy up to ~1.7* 103 mm2/s. Tumor Tumor #12;Sodium MRI of Rodent Glioma at 21T National High Magnetic

Weston, Ken

11

Pulmonary Toxicity Studies of Lunar Dusts in Rodents  

NASA Technical Reports Server (NTRS)

NASA will build an outpost on the lunar surface for long-duration human habitation and research. The surface of the Moon is covered by a layer of fine, reactive dust, and the living quarters in the lunar outpost are expected to be contaminated by lunar dust. NASA established the Lunar Airborne Dust Toxicity Advisory Group (LADTAG) to evaluate the risk of exposure to the dust and to establish safe exposure limits for astronauts working in the lunar habitat. Because the toxicity of lunar dust is not known, LADTAG has recommended investigating its toxicity in the lungs of laboratory animals. After receiving this recommendation, NASA directed the JSC Toxicology Laboratory to determine the pulmonary toxicity of lunar dust in exposed rodents. The rodent pulmonary toxicity studies proposed here are the same as those proposed by the LADTAG. Studies of the pulmonary toxicity of a dust are generally done first in rodents by intratracheal instillation (ITI). This toxicity screening test is then followed by an inhalation study, which requires much more of the test dust and is labor intensive. We succeeded in completing an ITI study on JSC-1 lunar dust simulant in mice (Lam et al., Inhalation Toxicology 14:901-916, 2002, and Inhalation Toxicology 14: 917-928, 2002), and have conducted a pilot ITI study to examine the acute toxicity of an Apollo lunar (highland) dust sample. Preliminary results obtained by examining lung lavage fluid from dust-treated mice show that lunar dust was somewhat toxic (more toxic than TiO2, but less than quartz dust). More extensive studies have been planned to further examine lung lavage fluid for biomarkers of toxicity and lung tissues for histopathological lesions in rodents exposed to aged and activated lunar dust samples. In these studies, reference dusts (TiO2 and quartz) of known toxicities and have industrial exposure limits will be studied in parallel so the relative toxicity of lunar dust can be determined. The ITI results will also be useful for choosing an exposure concentration for the animal inhalation study on a selected lunar dust sample, which is included as a part of this proposal. The animal inhalation exposure will be conducted with lunar dust simulant prior to the study with the lunar dust. The simulant exposure will ensure that the study techniques used with actual lunar dust will be successful. The results of ITI and inhalation studies will reveal the toxicological risk of exposures and are essential for setting exposure limits on lunar dust for astronauts living in the lunar habitat.

Lam, Chiu-wing; James, John T.; Taylor, Larry

2008-01-01

12

Pulmonary Toxicity Studies of Lunar Dusts in Rodents  

NASA Technical Reports Server (NTRS)

NASA will build an outpost on the lunar surface for long-duration human habitation and research. The surface of the Moon is covered by a layer of fine, reactive dust, and the living quarters in the lunar outpost are expected to be contaminated by lunar dust. Because the toxicity of lunar dust is not known, NASA has tasked its toxicology laboratory to evaluate the risk of exposure to the dust and to establish safe exposure limits for astronauts working in the lunar habitat. Studies of the pulmonary toxicity of a dust are generally done first in rodents by intratracheal/intrapharyngeal instillation. This toxicity screening test is then followed by an inhalation study, which requires much more of the test dust and is labor intensive. Preliminary results obtained by examining lung lavage fluid from dust-treated mice show that lunar dust was somewhat toxic (more toxic than TiO2, but less than quartz dust). More extensive studies are in progress to further examine lung lavage fluid for biomarkers of toxicity and lung tissues for histopathological lesions in rodents exposed to aged and activated (ground) lunar dust samples. In these studies, reference dusts (TiO2 and quartz) of known toxicities and have industrial exposure limits will be studied in parallel so the relative toxicity of lunar dust can be determined. The results from the instillation studies will be useful for choosing exposure concentrations for the animal inhalation study. The animal inhalation exposure will be conducted with lunar dust simulant prior to the study with the lunar dust. The experiment with the simulate will ensure that the study techniques used with actual lunar dust will be successful. The results of instillation and inhalation studies will reveal the toxicological risk of exposures and are essential for setting exposure limits on lunar dust for astronauts living in the lunar habitat.

Lam, Chiu-wing; James, John T.

2009-01-01

13

The rodent estrous cycle: Characterization of vaginal cytology and its utility in toxicological studies  

EPA Science Inventory

An evaluation of the estrous cycle in laboratory rodents can be a useful measure of the integrity of the hypothalamic-pituitary-ovarian reproductive axis. It can also serve as a way of insuring that animals exhibiting abnormal cycling patterns are disincluded from a study prior t...

14

Laboratory and field evaluation of rodent bait treated with fipronil for feed through and systemic control of Phlebotomus papatasi.  

PubMed

The sand fly Phlebotomus papatasi is the main vector of Leishmania major, etiologic agent of zoonotic cutaneous leishmaniasis (ZCL), which is endemic in North Africa, the Middle East, and Asia. In North Africa, Meriones shawi is one of the two main reservoir hosts of L. major. P. papatasi populations are maintained in borrowing rodents such as M. shawi. Three fipronil-treated rodent baits were evaluated for systemic and feed through insecticidal activity against P. papatasi feeding on M. shawi. Through blood feeding bioassays, mortality rates of females P. papatasi increased with the concentration of fipronil in the rodent bait varying from 0.001% to 0.005%. In the laboratory, more than 90.0% of P. papatasi were killed within 48h after blood feeding on the desert's jirds, M. shawi, treated up to 29 days prior with a single application of fipronil at a concentration of 0.001%, 0.0025% and 0.005%. Through larval bioassays, mortality rates of larvae that have fed on faeces of treated bait for M. shawi increase with the concentrations of fipronil. Faeces of orally-treated Meriones were significantly toxic to larvae for 5 weeks with a concentration of 0.005%. In the field, application of treated bait resulted in 80.0% reduction in the populations of P. papatasi up to 6 weeks after a single application of fipronil at a concentration of 0.005%. This is the first study to demonstrate field efficacy of fipronil-treated rodent baits for P. papatasi control and the first study to evaluate this approach in M. shawi, a principal ZCL reservoir host. These results suggest that fipronil-treated rodent baits can be used to effectively reduce the populations of P. papatasi associated with M. shawi in ZCL endemic areas. PMID:24681222

Derbali, M; Polyakova, L; Boujaâma, A; Burruss, D; Cherni, S; Barhoumi, W; Chelbi, I; Poché, R; Zhioua, E

2014-07-01

15

Rodents for comparative aging studies: from mice to beavers  

PubMed Central

After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents. PMID:19424861

Bozzella, Michael J.; Seluanov, Andrei

2008-01-01

16

The role of pheromonal responses in rodent behavior: future directions for the development of laboratory protocols.  

PubMed

Pheromones--chemical signals that can elicit responses in a conspecific--are important in intraspecies communication. Information conveyed by pheromones includes the location of an animal, the presence of food or a threat, sexual attraction, courtship, and dam-pup interactions. These chemical messages remain intact and volatile even when animals, such as rodents, are housed in laboratories rather than their natural environment. Laboratory protocols, such as the cage cleaning and sanitation processes, as well as general housing conditions can alter a rodent's normal production of pheromones in both amount and type and thus may affect behavior. In addition, some procedures induce the release of alarm pheromones that subsequently alter the behavior of other rodents. To prevent pheromonal interference and stress-induced pheromonal release in their research subjects, experimenters should assess current laboratory protocols regarding cage cleaning processes, housing designs, and behavioral assays. Here we discuss how the most commonly used laboratory procedures can alter pheromonal signaling and cause confounding effects. PMID:23562094

Bind, Rebecca H; Minney, Sarah M; Rosenfeld, SaraJane; Hallock, Robert M

2013-03-01

17

The Role of Pheromonal Responses in Rodent Behavior: Future Directions for the Development of Laboratory Protocols  

PubMed Central

Pheromones—chemical signals that can elicit responses in a conspecific—are important in intraspecies communication. Information conveyed by pheromones includes the location of an animal, the presence of food or a threat, sexual attraction, courtship, and dam–pup interactions. These chemical messages remain intact and volatile even when animals, such as rodents, are housed in laboratories rather than their natural environment. Laboratory protocols, such as the cage cleaning and sanitation processes, as well as general housing conditions can alter a rodent's normal production of pheromones in both amount and type and thus may affect behavior. In addition, some procedures induce the release of alarm pheromones that subsequently alter the behavior of other rodents. To prevent pheromonal interference and stress-induced pheromonal release in their research subjects, experimenters should assess current laboratory protocols regarding cage cleaning processes, housing designs, and behavioral assays. Here we discuss how the most commonly used laboratory procedures can alter pheromonal signaling and cause confounding effects. PMID:23562094

Bind, Rebecca H; Minney, Sarah M; Rosenfeld, SaraJane; Hallock, Robert M

2013-01-01

18

Sex Differences in Behavioral Circadian Rhythms in Laboratory Rodents  

PubMed Central

There is a strong bias in basic research on circadian rhythms toward the use of only male animals in studies. Furthermore, of the studies that use female subjects, many use only females and do not compare results between males and females. This review focuses on behavioral aspects of circadian rhythms that differ between the sexes. Differences exist in the timing of daily onset of activity, responses to both photic and non-photic stimuli, and in changes across the lifespan. These differences may reflect biologically important traits that are ecologically relevant and impact on a variety of responses to behavioral and physiological challenges. Overall, more work needs to be done to investigate differences between males and females as well as differences that are the result of hormonal changes across the lifespan.

Krizo, Jessica A.; Mintz, Eric M.

2014-01-01

19

CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS  

EPA Science Inventory

CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS. WP Watkinson1, LB Wichers2, JP Nolan1, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, LC Walsh1, ER Lappi1, D Terrell1, R Slade1, AD Ledbetter1, and DL Costa1. 1USEPA, ORD/NHEERL/ETD/PTB, RTP, NC, US...

20

A Bead-Based Multiplex Assay for the Detection of DNA Viruses Infecting Laboratory Rodents  

PubMed Central

The Federation of European Laboratory Animal Science Association (FELASA) recommends screening of laboratory rodents and biological materials for a broad variety of bacterial agents, viruses, and parasites. Methods commonly used to date for pathogen detection are neither cost-effective nor time- and animal-efficient or uniform. However, an infection even if silent alters experimental results through changing the animals’ physiology and increases inter-individual variability. As a consequence higher numbers of animals and experiments are needed for valid and significant results. We developed a novel high-throughput multiplex assay, called rodent DNA virus finder (rDVF) for the simultaneous identification of 24 DNA viruses infecting mice and rats. We detected all 24 DNA viruses with high specificity and reproducibility. Detection limits for the different DNA viruses varied between 10 and 1000 copies per PCR. The validation of rDVF was done with DNA isolated from homogenised organs amplified by pathogen specific primers in one multiplex PCR. The biotinylated amplicons were detected via hybridisation to specific oligonucleotide probes coupled to spectrally distinct sets of fluorescent Luminex beads. In conclusion, rDVF may have the potential to replace conventional testing and may simplify and improve routine detection of DNA viruses infecting rodents. PMID:24835244

Höfler, Daniela; Nicklas, Werner; Mauter, Petra; Pawlita, Michael; Schmitt, Markus

2014-01-01

21

Rodent Models and Imaging Techniques to Study Liver Regeneration.  

PubMed

The liver has the unique capability of regeneration from various injuries. Different animal models and in vitro methods are used for studying the processes and mechanisms of liver regeneration. Animal models were established either by administration of hepatotoxic chemicals or by surgical approach. The administration of hepatotoxic chemicals results in the death of liver cells and in subsequent hepatic regeneration and tissue repair. Surgery includes partial hepatectomy and portal vein occlusion or diversion: hepatectomy leads to compensatory regeneration of the remnant liver lobe, whereas portal vein occlusion leads to atrophy of the ipsilateral lobe and to compensatory regeneration of the contralateral lobe. Adaptation of modern radiological imaging technologies to the small size of rodents made the visualization of rodent intrahepatic vascular anatomy possible. Advanced knowledge of the detailed intrahepatic 3D anatomy enabled the establishment of refined surgical techniques. The same technology allows the visualization of hepatic vascular regeneration. The development of modern histological image analysis tools improved the quantitative assessment of hepatic regeneration. Novel image analysis tools enable us to quantify reliably and reproducibly the proliferative rate of hepatocytes using whole-slide scans, thus reducing the sampling error. In this review, the refined rodent models and the newly developed imaging technology to study liver regeneration are summarized. This summary helps to integrate the current knowledge of liver regeneration and promises an enormous increase in hepatological knowledge in the near future. © 2014 S. Karger AG, Basel. PMID:25402256

Wei, Weiwei; Dirsch, Olaf; Lawson Mclean, Anna; Zafarnia, Sara; Schwier, Michael; Dahmen, Uta

2014-11-12

22

Two new rodent models for actinide toxicity studies. [/sup 237/Pu, /sup 241/Am  

SciTech Connect

Two small rodent species, the grasshopper mouse (Onychomys leucogaster) and the deer mouse (Peromyscus maniculatus), have tenacious and high retention in the liver and skeleton of plutonium and americium following intraperitoneal injection of Pu and Am in citrate solution. Liver retention of Pu and Am in the grasshopper mouse is higher than liver retention in the deer mouse. Both of these rodents are relatively long-lived, breed well in captivity, and adapt suitably to laboratory conditions. It is suggested that these two species of mice, in which plutonium retention is high and prolonged in both the skeleton and liver, as it is in man, may be useful animal models for actinide toxicity studies.

Taylor, G.N.; Jones, C.W.; Gardner, P.A.; Lloyd, R.D.; Mays, C.W.; Charrier, K.E.

1981-04-01

23

Genetic structure and inter-generic relationship of closed colony of laboratory rodents based on RAPD markers.  

PubMed

Molecular genetic analysis was performed using random amplified polymorphic DNA (RAPD) on three commonly used laboratory bred rodent genera viz. mouse (Mus musculus), rat (Rattus norvegicus) and guinea pig (Cavia porcellus) as sampled from the breeding colony maintained at the Animal Facility, CSIR-Indian Institute of Toxicology Research, Lucknow. In this study, 60 samples, 20 from each genus, were analyzed for evaluation of genetic structure of rodent stocks based on polymorphic bands using RAPD markers. Thirty five random primers were assessed for RAPD analysis. Out of 35, only 20 primers generated a total of 56.88% polymorphic bands among mice, rats and guinea pigs. The results revealed significantly variant and distinct fingerprint patterns specific to each of the genus. Within-genera analysis, the highest (89.0%) amount of genetic homogeneity was observed in mice samples and the least (79.3%) were observed in guinea pig samples. The amount of genetic homogeneity was observed very high within all genera. The average genetic diversity index observed was low (0.045) for mice and high (0.094) for guinea pigs. The inter-generic distances were maximum (0.8775) between mice and guinea pigs; and the minimum (0.5143) between rats and mice. The study proved that the RAPD markers are useful as genetic markers for assessment of genetic structure as well as inter-generic variability assessments. PMID:25074272

Kumar, Mahadeo; Kumar, Sharad

2014-11-01

24

Comparison of Birth-and Conception-Based Definitions of Postnatal Age in Developmental and Reproductive Rodent Toxicity Studies: Influence of Gestation Length and Timing of Neonatal Examinations on Litter Data in Controls  

EPA Science Inventory

Laboratories conducting developmental and reproductive toxicity studies with rodents use varied protocols for determining the timing of neonatal litter examinations and subsequent measurements. Most laboratories determine timing based on the day of birth (DOB); l.e., gestation le...

25

Mammary gland neoplasia in long-term rodent studies.  

PubMed Central

Breast cancer, the most frequent spontaneous malignancy diagnosed in women in the western world, is continuously increasing in incidence in industrialized nations. Although breast cancer develops in women as the result of a combination of external and endogenous factors such as exposure to ionizing radiation, diet, socioeconomic status, and endocrinologic, familial, or genetic factors, no specific etiologic agent(s) or the mechanisms responsible of the disease has been identified as yet. Thus, experimental models that exhibit the same complex interactions are needed for testing various mechanisms and for assessing the carcinogenic potential of given chemicals. Rodent mammary carcinomas represent such a model to a great extent because, in these species, mammary cancer is a multistep complex process that can be induced by either chemicals, radiation, viruses, or genetic factors. Long-term studies in rodent models have been particularly useful for dissecting the initiation, promotion, and progression steps of carcinogenesis. The susceptibility of the rodent mammary gland to develop neoplasms has made this organ a unique target for testing the carcinogenic potential of specific genotoxic chemicals and environmental agents. Mammary tumors induced by indirect- or direct-acting carcinogens such as 7, 12-dimethlbenz(a)anthracene or N-methyl-N-nitrosourea are, in general, hormone dependent adenocarcinomas whose incidence, number of tumors per animal, tumor latency, and tumor type are influenced by the age, reproductive history, and endocarinologic milieu of the host at the time of carcinogen exposure. Rodent models are informative in the absence of human data. They have provided valuable information on the dose and route of administration to be used and optimal host conditions for eliciting maximal tumorigenic response. Studies of the influence of normal gland development on the pathogenesis of chemically induced mammary carcinomas have clarified the role of differentiation in cancer initiation. Comparative studies with the development of the human breast and the pathogenesis of breast cancer have contributed to validate rodent-to-human extrapolations. However, it has not been definitively established what type of information is necessary for human risk assessment, whether currently toxicity testing methodologies are sufficient for fulfilling those needs, or whether treatment-induced tumorigenic responses in rodents are predictive of potential human risk. An alternative to the traditional bioassays are mechanism-based toxicology and molecular and cellular approaches, combined with comparative in vitro systems. These approaches might allow the rapid screen of chemicals for setting priorities for further studies to determine the dose-response relationship for chemical effects at low doses, to assess effects other than mutagenesis and/or tumorigenesis, or to establish qualitative and quantitative relationships of biomarkers to toxic effects. Until there is enough information on the predictive value of mechanism-based toxicology for risk assessment, this approach should be used in conjunction with and validated by the traditional in vivo long-term bioassays. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. A Figure 7. B Figure 8. A Figure 8. B Figure 9. Figure 10. Figure 11. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23. Figure 24. Figure 25. Figure 26. PMID:8899375

Russo, I H; Russo, J

1996-01-01

26

Teaching Laboratory Rodent Research Techniques under the Tenets of Situated Learning Improves Student Confidence and Promotes Collaboration  

PubMed Central

A targeted needs assessment at our institution revealed that the online system used to train researchers on performing techniques with animals did not provide opportunities to practice skills, introduce learners to animal care staff, nor satisfactorily support researchers’ needs to become comfortable with laboratory animal species. To correct these deficiencies, a series of hands-on training sessions, framed theoretically in situated learning, was developed. This theoretical framework asserts that learning for everyday living (in this case, performing laboratory animal techniques) happens when people interact within the community while using the ‘tools at hand’ (that is, the instruments and jargon of the field). From this perspective, the students work alongside the instructor as apprentices. The instructor creates increasingly challenging learning opportunities as students work toward independently performing techniques. To test our hypothesis that teaching from this perspective improves comfort levels with laboratory animals and promotes collaborative relationships between animal care and research personnel, a mixed-method design involving online surveys (first survey, n = 45; second survey, n = 35) and semistructured interviews (n = 10) was used. Quantitative results revealed that students became more comfortable with laboratory animals and were more likely to contact animal care personnel due to participating in the training program. The qualitative arm of the study identified specific features of the training program that improved comfort levels for students (seeing then doing, working in small groups, learning within a comfortable environment, and building collegial relationships). These results support teaching rodent research techniques from the practical and theoretical approach of situated learning. PMID:25199092

Whitcomb, Tiffany L; Taylor, Edward W

2014-01-01

27

A survey of rodent-borne pathogens carried by wild-caught Norway rats: a potential threat to laboratory rodent colonies.  

PubMed

Unintentional infection of laboratory rodents can compromise scientific research as well as the health of the animals and animal handlers. The source of contamination often is unknown, but may be introduced by wild rats from surrounding environments. To determine whether rats in Baltimore, Maryland, USA carry infectious agents commonly found in laboratory rodent colonies, we live-trapped 162 rats during 2005 to 2006 and screened them for a panel of viruses, bacteria and parasites. Antibodies against rat coronavirus/sialodacryoadenitis virus (91.7%), Mycoplasma pulmonis (72.9%), cilia-associated respiratory bacillus (52.1%), rat parvovirus/rat minute virus (29.2%), Kilham rat virus (10.4%), Toolan's H-1 virus (10.4%), Sendai virus (4.2%) and Theiler's mouse encephalomyelitis virus (4.2%), were detected in wild-caught Norway rats. Antibodies against reovirus and pneumonia virus of mice were not detected in wild Norway rats. Endoparasites, including Nippostrongylus braziliensis (71.6%), Rodentolepis nana or Hymenolepis diminuta (34.4%), Hetarakis spumosa (24.1%) and Trichuris muris (14.8%), as well as ectoparasites (14.8%), were identified in wild-caught rats. The risk of pathogen transmission from wild-caught rats to laboratory colonies needs to be mitigated by minimizing exposures rather than assuming wild animals represent a minimal hazard. PMID:18348770

Easterbrook, Judith D; Kaplan, J B; Glass, G E; Watson, J; Klein, S L

2008-01-01

28

Studying Autism in Rodent Models: Reconciling Endophenotypes with Comorbidities  

PubMed Central

Autism spectrum disorder (ASD) patients commonly exhibit a variety of comorbid traits including seizures, anxiety, aggressive behavior, gastrointestinal problems, motor deficits, abnormal sensory processing, and sleep disturbances for which the cause is unknown. These features impact negatively on daily life and can exaggerate the effects of the core diagnostic traits (social communication deficits and repetitive behaviors). Studying endophenotypes relevant to both core and comorbid features of ASD in rodent models can provide insight into biological mechanisms underlying these disorders. Here we review the characterization of endophenotypes in a selection of environmental, genetic, and behavioral rodent models of ASD. In addition to exhibiting core ASD-like behaviors, each of these animal models display one or more endophenotypes relevant to comorbid features including altered sensory processing, seizure susceptibility, anxiety-like behavior, and disturbed motor functions, suggesting that these traits are indicators of altered biological pathways in ASD. However, the study of behaviors paralleling comorbid traits in animal models of ASD is an emerging field and further research is needed to assess altered gastrointestinal function, aggression, and disorders of sleep onset across models. Future studies should include investigation of these endophenotypes in order to advance our understanding of the etiology of this complex disorder. PMID:23898259

Argyropoulos, Andrew; Gilby, Krista L.; Hill-Yardin, Elisa L.

2013-01-01

29

Anaesthesia and physiological monitoring during in vivo imaging of laboratory rodents: considerations on experimental outcomes and animal welfare  

PubMed Central

The implementation of imaging technologies has dramatically increased the efficiency of preclinical studies, enabling a powerful, non-invasive and clinically translatable way for monitoring disease progression in real time and testing new therapies. The ability to image live animals is one of the most important advantages of these technologies. However, this also represents an important challenge as, in contrast to human studies, imaging of animals generally requires anaesthesia to restrain the animals and their gross motion. Anaesthetic agents have a profound effect on the physiology of the animal and may thereby confound the image data acquired. It is therefore necessary to select the appropriate anaesthetic regime and to implement suitable systems for monitoring anaesthetised animals during image acquisition. In addition, repeated anaesthesia required for longitudinal studies, the exposure of ionising radiations and the use of contrast agents and/or imaging biomarkers may also have consequences on the physiology of the animal and its response to anaesthesia, which need to be considered while monitoring the animals during imaging studies. We will review the anaesthesia protocols and monitoring systems commonly used during imaging of laboratory rodents. A variety of imaging modalities are used for imaging rodents, including magnetic resonance imaging, computed tomography, positron emission tomography, single photon emission computed tomography, high frequency ultrasound and optical imaging techniques such as bioluminescence and fluorescence imaging. While all these modalities are implemented for non-invasive in vivo imaging, there are certain differences in terms of animal handling and preparation, how the monitoring systems are implemented and, importantly, how the imaging procedures themselves can affect mammalian physiology. The most important and critical adverse effects of anaesthetic agents are depression of respiration, cardiovascular system disruption and thermoregulation. When anaesthetising rodents, one must carefully consider if these adverse effects occur at the therapeutic dose required for anaesthesia, if they are likely to affect the image acquisitions and, importantly, if they compromise the well-being of the animals. We will review how these challenges can be successfully addressed through an appropriate understanding of anaesthetic protocols and the implementation of adequate physiological monitoring systems. PMID:22877315

2012-01-01

30

Euthanasia by decapitation: evidence that this technique produces prompt, painless unconsciousness in laboratory rodents.  

PubMed

Rapid euthanasia of laboratory rodents without the use of anesthesia is a necessary research technique whenever there is the likelihood of anesthesia or stress interfering with the chemistry of the tissues under investigation. Decapitation has long been the procedure of choice under such circumstances. Recently, however, the American Veterinary Medical Association (AVMA) panel on euthanasia recommended that decapitation be avoided on the grounds that the decapitated head may be conscious and suffering for as much as 15 seconds. The panel further recommended that if decapitation was scientifically necessary, the decapitated head be immediately immersed in liquid nitrogen. These AVMA guidelines now enjoy regulatory status; the recommendation that decapitation be avoided has thus caused considerable difficulty for all research requiring rapid, anesthesia-free collection of tissues. The scientific validity of these recommendations is consequently a matter of great practical as well as theoretical importance. The decision to discourage decapitation appears to have been based on a single literature report claiming that the EEG of the decapitated head revealed conscious suffering for more than 10 seconds (Mikeska and Klemm 1976). This review carefully examines the scientific literature on this subject. It is concluded that the report by Mikeska and Klemm of EEG activation in the decapitated head is correct, but that this phenomenon is also seen when the decapitated head is under deep anesthesia, and in normal brains under ether anesthesia or during REM sleep. Hence these findings do not demonstrate either consciousness or the perception of pain.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1522830

Holson, R R

1992-01-01

31

STUDY OF THE CHEMICAL AND BEHAVIORAL TOXICOLOGY OF SUBSTITUTE CHEMICALS IN MICROTINE RODENTS  

EPA Science Inventory

Acute oral LD50 and 30-day dietary subacute LC50 studies of 10 selected pesticides were evaluated in microtine rodents. As a means to developing new animal model systems, four species of microtine rodents including Microtus ochrogaster (MO), Microtus canicaudus (MC), Microtus pen...

32

OCT-aided anastomosis platform study in the rodent model  

NASA Astrophysics Data System (ADS)

Anastomosis is one of the most commonly performed procedure in the clinical environment that involves tubular structures, such as blood vessel, lymphatic vessel, seminal duct and ureter. Suture based anastomosis is still the foundation for most basic surgical training and clinical operation, although alternate techniques have been developed and under development. For those tubular-structure-anastomosis, immediate real-time post-operative evaluation of the surgical outcome is critical to the success of surgery. Previously evaluation is mostly based on surgeons' experience. Fourier-domain optical coherence tomography is high-speed, high-resolution noninvasive 3D imaging modality that has been widely used in the biomedical research and clinical study. In this study we used Fourier-domain optical coherence tomography as an evaluation tool for anastomosis of lymphatic vessels, ureter and seminal duct in rodent model. Immediate post-operative and long term surgical site data were collected and analyzed. Critical clinical parameters such as lumen patency, anastomosed site narrowing and suture error detection are provided to surgeons.

Huang, Yong; Tong, Dedi; Zhu, Shan; Wu, Lehao; Ibrahim, Zuhaib; Lee, WP Andrew; Brandacher, Gerald; Kang, Jin U.

2014-02-01

33

A new rodent behavioral paradigm for studying forelimb movement  

PubMed Central

The center-out task is a standard paradigm often used to study the neural control of reaching movements in human and non-human primates. However, there are several disadvantages to the use of monkeys, notably costs, infrastructural requirements, and ethical considerations. Here we describe a similar task designed to examine forelimb movements in rats. Rats were trained to grasp a joystick with their forepaw and use it to control the movements of a sipper tube in two dimensions. The rats learned to move the joystick in four directions with at least 70% accuracy after about 45 days of training. In addition, rats were able to learn a reversed mapping between joystick and sipper tube movement. This is a more complicated behavior than has been previously demonstrated for rats, and it could allow more motor behavior studies to be conducted in rodents instead of monkeys. We currently are using this behavior to decode the rats’ forelimb movements from their brain signals. PMID:20691727

Slutzky, Marc W.; Jordan, Luke R.; Bauman, Matthew J.; Miller, Lee E.

2010-01-01

34

How-to-Do-It: Laboratory Projects on Defensive Burying by Rodents.  

ERIC Educational Resources Information Center

Described are the basic materials and procedures used to study defensive burying behavior and suggested laboratory projects. Discusses live targets, non-living targets, social variables, and previous experiences of the subjects. (CW)

Meek, Leslie R.; And Others

1988-01-01

35

Lung Function Measurements in Rodents in Safety Pharmacology Studies  

PubMed Central

The ICH guideline S7A requires safety pharmacology tests including measurements of pulmonary function. In the first step – as part of the “core battery” – lung function tests in conscious animals are requested. If potential adverse effects raise concern for human safety, these should be explored in a second step as a “follow-up study”. For these two stages of safety pharmacology testing, both non-invasive and invasive techniques are needed which should be as precise and reliable as possible. A short overview of typical in vivo measurement techniques is given, their advantages and disadvantages are discussed and out of these the non-invasive head-out body plethysmography and the invasive but repeatable body plethysmography in orotracheally intubated rodents are presented in detail. For validation purposes the changes in the respective parameters such as tidal midexpiratory flow (EF50) or lung resistance have been recorded in the same animals in typical bronchoconstriction models and compared. In addition, the technique of head-out body plethysmography has been shown to be useful to measure lung function in juvenile rats starting from day two of age. This allows safety pharmacology testing and toxicological studies in juvenile animals as a model for the young developing organism as requested by the regulatory authorities (e.g., EMEA Guideline 1/2008). It is concluded that both invasive and non-invasive pulmonary function tests are capable of detecting effects and alterations on the respiratory system with different selectivity and area of operation. The use of both techniques in a large number of studies in mice and rats in the last years have demonstrated that they provide useful and reliable information on pulmonary mechanics in safety pharmacology and toxicology testing, in investigations of respiratory disorders, and in pharmacological efficacy studies. PMID:22973226

Hoymann, Heinz Gerd

2012-01-01

36

More than numbers matter: The effect of social factors on behaviour and welfare of laboratory rodents and non-human primates  

Microsoft Academic Search

With the development of laboratory animal science, increasing attention has been given to the possible influence of housing and husbandry on the behaviour and welfare of laboratory animals as well as on the scientific integrity. With the present paper, we aim to contribute to this knowledge by reviewing existing literature on how social factors influence laboratory rodents and non-human primates.

I. Anna S. Olsson; Karolina Westlund

2007-01-01

37

Rodent models for the study of articular fracture healing.  

PubMed

The goal of this study was to document the healing time course and expression of ex vivo cell-based gene delivery in articular fracture models in the mouse and rat. Articular medial intercondylar femoral osteotomy was performed in the stifle (knee) joints of hairless immunocompetent mice and medial or lateral similar osteotomy was performed in athymic nude rats. Genetically modified cells expressing luciferase were delivered in a three-dimensional alginate matrix directly into the osteotomy site. Sensitivity of an in vivo imaging system to detect expression of luciferase was compared between rodents in this fracture model. Osteotomy healing was assessed using high-detail radiography, helical computed tomography (CT), high-field magnetic resonance imaging, and histology. The mouse model was less satisfactory because the small size of the murine femur made reliable assessment of fracture healing restricted to histopathology, and complications occurred in 11/24 mice (45.8%), most frequently transverse supracondylar femoral fracture postoperatively. Gene expression was inconsistently confirmed in mice in vivo for 11 days (p < .003). In rats, high-detail radiography and CT were used to assess osteotomy healing. Magnetic resonance imaging (4.7 T) in rats could produce three-dimensional images that would permit assessment of bone and cartilage, but was time-consuming and expensive. In rats, the only surgical complication, transverse femoral fracture, was reduced from 83.3% with the medial osteotomy to 0% with a lateral osteotomy. In vivo imaging confirmed gene expression in the alginate/cell constructs in rats for at least 4 days (p < .05). The nude rat model has the advantage of larger femora and the ability to implant xenograft cells. A lateral intercondylar osteotomy of the distal femur in the rat can be used to study the healing of articular fractures. PMID:17454393

Zachos, Terri A; Bertone, Alicia L; Wassenaar, Peter A; Weisbrode, Steven E

2007-01-01

38

Electromechanical design of a body weight support system for a therapeutic robot for rodent studies  

E-print Network

As part of an ongoing effort to better understand and treat locomotor disorders, an over-ground therapeutic robot prototype to study recovery of locomotion after spinal cord injury in rodents is under development. One key ...

Mayalu, Michaëlle Ntala

2010-01-01

39

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

Variable Gravity Laboratory studies are discussed. The following subject areas are covered: (1) conceptual design and engineering analysis; (2) control strategies (fast crawling maneuvers, main perturbations and their effect upon the acceleration level); and (3) technology requirements.

Lucchetti, F.

1989-01-01

40

Cryptosporidium spp. in Wild, Laboratory, and Pet Rodents in China: Prevalence and Molecular Characterization? †  

PubMed Central

To understand the prevalence of Cryptosporidium infection in rodents in China and to assess the potential role of rodents as a source for human cryptosporidiosis, 723 specimens from 18 rodent species were collected from four provinces of China and examined between August 2007 and December 2008 by microscopy after using Sheather's sugar flotation and modified acid-fast staining. Cryptosporidium oocysts were detected in 83 specimens, with an overall prevalence of 11.5%. Phodopus sungorus, Phodopus campbelli, and Rattus tanezumi were new reported hosts of Cryptosporidium. The genotypes and subtypes of Cryptosporidium strains in microscopy-positive specimens were further identified by PCR and sequence analysis of the small subunit rRNA and the 60-kDa glycoprotein (gp60) genes. In addition to Cryptosporidium parvum, C. muris, C. andersoni, C. wrairi, ferret genotype, and mouse genotype I, four new Cryptosporidium genotypes were identified, including the hamster genotype, chipmunk genotype III, and rat genotypes II and III. Mixed Cryptosporidium species/genotypes were found in 10.8% of Cryptosporidium-positive specimens. Sequence analysis of the gp60 gene showed that C. parvum strains in pet Siberian chipmunks and hamsters were all of the subtype IIdA15G1, which was found previously in a human isolate in The Netherlands and lambs in Spain. The gp60 sequences of C. wrairi and the Cryptosporidium ferret genotype and mouse genotype I were also obtained. These findings suggest that pet rodents may be potential reservoirs of zoonotic Cryptosporidium species and subtypes. PMID:19820152

Lv, Chaochao; Zhang, Longxian; Wang, Rongjun; Jian, Fuchun; Zhang, Sumei; Ning, Changshen; Wang, Helei; Feng, Chao; Wang, Xinwei; Ren, Xupeng; Qi, Meng; Xiao, Lihua

2009-01-01

41

Studies on the life history and development of Cuterebra polita (Diptera: Cuterebridae) in four species of rodents  

USGS Publications Warehouse

Cuterebra polita Coquillett is a primary parasite of the pocket gopher, Thomomys talpoides, in the western United States. It also occurs secondarily in other wild rodents that come into close contact with pocket gophers.Field studies disclosed pursuit, mating, and ovipositing at an aggregation site near Monte Cristo, Utah. Eggs were individually attached to fibrous roots suspended from the roof of shallow gopher burrows. This refinement of the host-parasite relationship has not previously been described for other North American cuterebrids.In the laboratory, 3 gravid females produced 186-357 viable eggs; about 85% were induced to hatch or hatched spontaneously after 12 days. Dissection of 1 of the females revealed another 886 eggs, for a total of 1243.Larvae were artificially introduced and developed in deer mice (Peromyscus maniculatus), domestic mice (Mus musculus), hamsters (Mesocricetus auratus), and meadow voles (Microtus montanus). The domestic rabbit (Orystolagus cuniculus) appeared refractory. The rate and success of development in the 4 rodent species was variable, but terminal larval development averaged about 22 days. Warbles appeared after 8 days in the rodents, and the majority of the cysts occurred in the posterior dorsal region.On the basis of larval characteristics, C. polita and C. thomomuris appear to be independent, valid species, though they share a common host.

Capelle, K.J.

1970-01-01

42

The Effects of Prenatal Alcohol Exposure on Behavior: Rodent and Primate Studies  

PubMed Central

The use of alcohol by women during pregnancy is a continuing problem. In this review the behavioral effects of prenatal alcohol from animal models are described and related to studies of children and adults with FASD. Studies with monkeys and rodents show that prenatal alcohol exposure adversely affects neonatal orienting, attention and motor maturity, as well as activity level, executive function, response inhibition, and sensory processing later in life. The primate moderate dose behavioral findings fill an important gap between human correlational data and rodent mechanistic research. These animal findings are directly translatable to human findings. Moreover, primate studies that manipulated prenatal alcohol exposure and prenatal stress independently show that prenatal stress exacerbates prenatal alcohol-induced behavioral impairments, underscoring the need to consider stress-induced effects in fetal alcohol research. Studies in rodents and primates show long-term effects of prenatal and developmental alcohol exposure on dopamine system functioning, which could underpin the behavioral effects. PMID:21499982

Moore, Colleen F.; Adkins, Miriam M.

2014-01-01

43

Laboratory microfusion capability study  

NASA Astrophysics Data System (ADS)

The purpose of this study is to elucidate the issues involved in developing a Laboratory Microfusion Capability (LMC) which is the major objective of the Inertial Confinement Fusion (ICF) program within the purview of the Department of Energy's Defense Programs. The study was initiated to support a number of DOE management needs: to provide insight for the evolution of the ICF program; to afford guidance to the ICF laboratories in planning their research and development programs; to inform Congress and others of the details and implications of the LMC; to identify criteria for selection of a concept for the Laboratory Microfusion Facility; and to develop a coordinated plan for the realization of an LMC. As originally proposed, the LMC study was divided into two phases. The first phase identifies the purpose and potential utility of the LMC, the regime of its performance parameters, driver independent design issues and requirements, its development goals and requirements, and associated technical, management, staffing, environmental, and other developmental and operational issues. The second phase addresses driver-dependent issues such as specific design, range of performance capabilities, and cost. The study includes four driver options: the neodymium-glass solid state laser, the krypton fluoride excimer gas laser, the light-ion accelerator, and the heavy-ion induction linear accelerator. The results of the Phase 2 study are described in the present report.

1993-05-01

44

Laboratory microfusion capability study  

SciTech Connect

The purpose of this study is to elucidate the issues involved in developing a Laboratory Microfusion Capability (LMC) which is the major objective of the Inertial Confinement Fusion (ICF) program within the purview of the Department of Energy's Defense Programs. The study was initiated to support a number of DOE management needs: to provide insight for the evolution of the ICF program; to afford guidance to the ICF laboratories in planning their research and development programs; to inform Congress and others of the details and implications of the LMC; to identify criteria for selection of a concept for the Laboratory Microfusion Facility and to develop a coordinated plan for the realization of an LMC. As originally proposed, the LMC study was divided into two phases. The first phase identifies the purpose and potential utility of the LMC, the regime of its performance parameters, driver independent design issues and requirements, its development goals and requirements, and associated technical, management, staffing, environmental, and other developmental and operational issues. The second phase addresses driver-dependent issues such as specific design, range of performance capabilities, and cost. The study includes four driver options; the neodymium-glass solid state laser, the krypton fluoride excimer gas laser, the light-ion accelerator, and the heavy-ion induction linear accelerator. The results of the Phase II study are described in the present report.

Not Available

1993-05-01

45

Why Can’t Rodents Vomit? A Comparative Behavioral, Anatomical, and Physiological Study  

PubMed Central

The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity–key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed. PMID:23593236

Horn, Charles C.; Kimball, Bruce A.; Wang, Hong; Kaus, James; Dienel, Samuel; Nagy, Allysa; Gathright, Gordon R.; Yates, Bill J.; Andrews, Paul L. R.

2013-01-01

46

Pulmonary Toxicity Studies of Lunar Dusts in Rodents  

NASA Technical Reports Server (NTRS)

NASA will build an outpost on the Moon for prolonged human habitation and research. The lunar surface is covered by a layer of fine, reactive dust. Astronauts on the Moon will go in and out of the base for various activities, and will inevitably bring some dust into the living quarters. Depressurizing the airlock so that astronauts can exit for outdoor activities could also bring dust inside the airlock to the habitable area. Concerned about the potential health effects on astronauts exposed to airborne lunar dust, NASA directed the JSC Toxicology Laboratory to determine the pulmonary toxicity of lunar dust. The toxicity data also will be needed by toxicologists to establish safe exposure limits for astronauts residing in the lunar habitat and by environmental engineers to design an appropriate dust mitigation strategy. We conducted a study to examine biomarkers of toxicity (inflammation and cytotoxicity) in lung lavage fluids from mice intrapharyngeally instilled with lunar dust samples; we also collected lung tissue from the mice for histopathological examination 3 months after the dust instillation. Reference dusts (TiO2 and quartz) having known toxicities and industrial exposure limits were studied in parallel with lunar dust so that the relative toxicity of lunar dust can be determined. A 6-month histopathology study has been planned. These instillation experiments will be followed by inhalation studies, which are more labor intensive and technologically difficult. The animal inhalation studies will be conducted first with an appropriate lunar dust simulant to ensure that the exposure techniques to be used with actual lunar dust will be successful. The results of these studies collectively will reveal the toxicological risk of exposures and enable us to establish exposure limits on lunar dust for astronauts living in the lunar habitat.

Lam, C.-W.; James, J. T.; Taylor, L.; Zeidler-Erdely, P. C.; Castranova, V.

2009-01-01

47

Draft Genome Sequences of Eight Enterohepatic Helicobacter Species Isolated from Both Laboratory and Wild Rodents  

E-print Network

The draft genome sequences of eight enterohepatic Helicobacter species, H. muridarum, H. trogontum, H. typhlonius, and five unnamed helicobacters, are presented here. Using laboratory mice pervasively infected with ...

Sheh, Alexander

48

Comparison of Birth-and Conception-Based Definitions of Postnatal Age in Developmental and Reproductive Rodent Toxicity Studies: lnfluence of Gestation Length on Measurements of Offspring Body Weight and Puberty in Controls  

EPA Science Inventory

Most laboratories conducting developmental and reproductive toxicity studies in rodents assign age by defining postnatal day (PND) 0 or 1 as the day of birth (DOB); i.e., gestation length affects PND and the timing of postnatal measurements. Some laboratories, however, define age...

49

Rodent-repellent studies. III. Advanced studies in the evaluation of chemical repellents  

USGS Publications Warehouse

In order to bridge the gap between preliminary screening of chemicals for potential rodent repellency and the application ofthese compounds to paper cartons, more advanced studies in the evaluation ofpromising materials have been carried out. These studies have resulted in: (1) a modification of the food acceptance technique which eliminates doubtful compounds and also provides a closer analogy to the ultimate goal, and (2) a method for rapidly testing chemicals incorporated in paper. When the results of these latter tests are expressed as a function of time, it can be shown that a distinct correlation exists between the deterrency exhibited by treated paper and the repellency of treated food.

Bellack, E.; DeWitt, J.B.

1949-01-01

50

MONITORING OF THE ESTROUS CYCLE IN THE LABORATORY RODENT BY VAGINAL LAVAGE  

EPA Science Inventory

Ovarian cyclicity in a number of laboratory species can be monitored easily and noninvasively by observing changes in the vaginal cytology. his chapter describes the techniques used to collect data in the laboratory rat and mouse and how to interpret the lavages as they are obtai...

51

AMPHETAMINE EFFECTS IN MICROTINE RODENTS: A COMPARATIVE STUDY USING MONOGAMOUS AND PROMISCUOUS VOLE SPECIES  

E-print Network

AMPHETAMINE EFFECTS IN MICROTINE RODENTS: A COMPARATIVE STUDY USING MONOGAMOUS AND PROMISCUOUS VOLE University, Tallahassee, FL 32306, USA Abstract--We compared amphetamine-induced dopamine re- lease dopamine after am- phetamine treatment than did promiscuous voles. We then examined whether amphetamine

Wang, Zuoxin

52

LONG-TERM EXPERIMENTAL STUDY OF A CHIHUAHUAN DESERT RODENT COMMUNITY: 13 YEARS OF COMPETITION  

Microsoft Academic Search

De11arrr)letzt of Blo\\/ogj I nrrersrri of \\\\ert Zleuco -Ilbi(querque \\\\el$ Mekrco 57131 C S,4 d4hstract. An experimental study of competition between kangaroo rats (Dipodornys spp.) and other sympatric desert rodents using exclosures with \\

EDWARD J HESKE; JAMES H BROWN; SHAHROUKH MISTRY

1994-01-01

53

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

The scope of the study is to investigate ways of controlling the microgravity environment of the International Space Station by means of a tethered system. Four main study tasks were performed. First, researchers analyzed the utilization of the tether systems to improve the lowest possible steady gravity level on the Space Station and the tether capability to actively control the center of gravity position in order to compensate for activities that would upset the mass distribution of the Station. The purpose of the second task was to evaluate the whole of the experiments performable in a variable gravity environment and the related beneficial residual accelerations, both for pure and applied research in the fields of fluid, materials, and life science, so as to assess the relevance of a variable g-level laboratory. The third task involves the Tethered Variable Gravity Laboratory. The use of the facility that would crawl along a deployed tether and expose experiments to varying intensities of reduced gravity is discussed. Last, a study performed on the Attitude Tether Stabilizer concept is discussed. The stabilization effect of ballast masses tethered to the Space Station was investigated as a means of assisting the attitude control system of the Station.

Lucchetti, F.

1990-01-01

54

VDTs: Field levels, epidemiology, and laboratory studies  

SciTech Connect

As the use of video display terminals (VDTs) has expanded, questions have been raised as to whether working at a VDT affects the risk of adverse pregnancy outcome. A particular focus for these questions has been the very low frequency (VLF) magnetic field produced by a VDT's horizontal deflection coil. VDTs also produce VLF electric fields, extremely low frequency (ELF) electric and magnetic fields, and static electric fields, Ten studies of pregnancy outcome in VDT operators have been conducted in six countries, and with one exception, none has concluded that magnetic fields from VDTs may predispose pregnant operators to spontaneous abortion or congenital malformation. The epidemiologic studies conducted thus far do not provide a basis for concluding that VDT work and adverse pregnancy outcome are associated. Studies of fetal resorptions and malformations in rodents exposed to VLF magnetic fields have produced inconsistent findings. Two laboratories in Sweden that studied mice have reported positive results, one laboratory showing field-related malformations (but not resorptions) and the other showing field-related resorptions (but not malformations). Two Canadian laboratories have reported negative results in rats and mice. Studies of avian embryos have also yielded inconsistent results, but lacking a maternal-fetal placental interface, avian embryos are a questionable model for evaluating human reproductive risks. Finally, VLF electric and magnetic fields measured at the operator position are in compliance with field strength standards and guidelines that have been established around the world. 55 refs.

Kavet, R.; Tell, R.A. (Richard Tell Associates, Inc., Las Vegas, NV (USA))

1991-07-01

55

A NEW METHOD TO QUANTIFY CORE TEMPERATURE INSTABILITY IN RODENTS.  

EPA Science Inventory

Methods to quantify instability of autonomic systems such as temperature regulation should be important in toxicant and drug safety studies. Stability of core temperature (Tc) in laboratory rodents is susceptible to a variety of stimuli. Calculating the temperature differential o...

56

Thirteen week rodent feeding study with processed fractions from herbicide tolerant (DP-Ø73496-4) canola.  

PubMed

The potential health effects of meal and oil processed from seed of genetically modified (GM) canola plants (OECD unique identifier: DP-Ø73496-4; hereafter referred to as 73496 canola) containing an insert that expresses the GAT4621 protein conferring tolerance to nonselective herbicidal ingredient glyphosate were evaluated in a subchronic rodent feeding study. Sprague-Dawley rats (12/sex/group) were administered diets containing dehulled, defatted toasted canola meal (DH meal) and refined/bleached/deodorized canola oil (RBD oil) processed from seed of plants that were untreated (73496), sprayed in-field with glyphosate (73496GLY), the non-transgenic near-isogenic (091; control), or one of four commercially available non-GM reference canola varieties (45H72, 45H73, 46A65, 44A89). All diets were formulated as a modification of the standard laboratory chow PMI® Nutrition International, LLC Certified Rodent LabDiet® 5002 (PMI® 5002). DH canola meal and RBD canola oil replaced all commodity soybean fractions typically incorporated in PMI® 5002. No toxicologically significant differences were observed between the test and control groups in this study. The results reported herein support the conclusion that DH meal and RBD oil processed from seed of 73496 canola are as safe and nutritious as DH meal and RBD oil processed from seed of non-GM canola. PMID:24491265

Delaney, Bryan; Appenzeller, Laura M; Roper, Jason M; Mukerji, Pushkor; Hoban, Denise; Sykes, Greg P

2014-04-01

57

In vivo MRI study of the visual system in normal, developing and injured rodent brains  

Microsoft Academic Search

This paper demonstrated our recent use of contrast-enhanced MRI, diffusion tensor\\/kurtosis imaging, proton magnetic resonance spectroscopy, and functional MRI techniques, for in vivo and global assessments of the structure, metabolism and function of the visual system in rodent studies of ocular diseases, optic neuropathies, developmental plasticity and neonatal hypoxic-ischemic brain injury at 7T. Results suggested the significant values of high-field

Kevin C. Chan; Matthew M. Cheung; Kyle K. Xing; Iris Y. Zhou; April M. Chow; Condon Lau; Kwok-fai So; Ed X. Wu

2010-01-01

58

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

The following subject areas are covered: (1) thermal control issues; (2) attitude control sybsystem; (3) configuration constraints; (4) payload; (5) acceleration requirements on Variable Gravity Laboratory (VGL); and (6) VGL configuration highlights.

Lucchetti, F.

1989-01-01

59

Rodents for comparative aging studies: from mice to beavers  

Microsoft Academic Search

After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research\\u000a has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and\\u000a rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal\\u000a is to further extend the

Vera Gorbunova; Michael J. Bozzella; Andrei Seluanov

2008-01-01

60

75 FR 80011 - Good Laboratory Practice for Nonclinical Laboratory Studies  

Federal Register 2010, 2011, 2012, 2013

...Laboratory Practice for Nonclinical Laboratory Studies AGENCY: Food and Drug Administration...to more completely address nonclinical studies as they are presently conducted, the...for conducting nonclinical laboratory studies that support or are intended to...

2010-12-21

61

Laboratory studies of interleaving  

Microsoft Academic Search

This is a review of laboratory experiments on double-diffusive interleaving. Several configurations are discussed and compared, including thermohaline fronts, heated sidewalls, melting ice-blocks, point heat sources, and double-diffusive plumes, using both the heat-salt and sugar-salt systems to generate property anomalies. Two parallels emerge. The vertical scale of intrusions in most configurations is proportional to the ‘natural’ scale given by the

B. Ruddick

2003-01-01

62

Laboratory studies of volcanic jets  

Microsoft Academic Search

The study of the fluid dynamics volcanic eruptions by laboratory experiment is described, and the important fluid-dynamic processes that can be examined in laboratory models are discussed in detail. In preliminary experiments, pure gases are erupted from small reservoirs. The gases used are Freon 12 and Freon 22, two gases of high molecular weight and high density that are good

Susan Werner Kieffer; Bradford Sturtevant

1984-01-01

63

Activity of and Effect of Subcutaneous Treatment with the Broad-Spectrum Antiviral Lectin Griffithsin in Two Laboratory Rodent Models  

PubMed Central

Griffithsin (GRFT) is a red-alga-derived lectin that binds the terminal mannose residues of N-linked glycans found on the surface of human immunodeficiency virus type 1 (HIV-1), HIV-2, and other enveloped viruses, including hepatitis C virus (HCV), severe acute respiratory syndrome coronavirus (SARS-CoV), and Ebola virus. GRFT displays no human T-cell mitogenic activity and does not induce production of proinflammatory cytokines in treated human cell lines. However, despite the growing evidence showing the broad-spectrum nanomolar or better antiviral activity of GRFT, no study has reported a comprehensive assessment of GRFT safety as a potential systemic antiviral treatment. The results presented in this work show that minimal toxicity was induced by a range of single and repeated daily subcutaneous doses of GRFT in two rodent species, although we noted treatment-associated increases in spleen and liver mass suggestive of an antidrug immune response. The drug is systemically distributed, accumulating to high levels in the serum and plasma after subcutaneous delivery. Further, we showed that serum from GRFT-treated animals retained antiviral activity against HIV-1-enveloped pseudoviruses in a cell-based neutralization assay. Overall, our data presented here show that GRFT accumulates to relevant therapeutic concentrations which are tolerated with minimal toxicity. These studies support further development of GRFT as a systemic antiviral therapeutic agent against enveloped viruses, although deimmunizing the molecule may be necessary if it is to be used in long-term treatment of chronic viral infections. PMID:24145548

Barton, Christopher; Kouokam, J. Calvin; Lasnik, Amanda B.; Foreman, Oded; Cambon, Alexander; Brock, Guy; Montefiori, David C.; Vojdani, Fakhrieh; McCormick, Alison A.; O'Keefe, Barry R.

2014-01-01

64

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

The use is studied of tether systems to improve the lowest possible steady gravity level on the Space Station. Particular emphasis is placed by the microgravity community on the achievement of high quality microgravity conditions. The tether capability is explored for active control of the center of gravity and the analysis of possible tethered configurations.

Lucchetti, F.

1989-01-01

65

ACTIVITY OF LM 2219 (DIFETHIALONE), A NEW ANTICOAGULANT RODENTICIDE, IN COMMENSAL RODENTS  

Microsoft Academic Search

Preliminary studies completed on commensal rodents with the new anticoagulant rodenticide difethialone showed very good efficacy, such that 25 ppm baits could be used effectively. New test results presented in this publication confirm the activity as shown under laboratory conditions in choice tests, which represent more severe conditions, as well as its effectiveness against rodents that are resistant and non-resistant

J. C. Lechevin; Richard M. Poche

1988-01-01

66

Studies on the immunobiology of infections with the metacestodes of Echinococcus multilocularis in rodents.  

E-print Network

??The relationships among parasite growth, responses to infection and host genetic factors were examined in rodents infected with Echinococcus multilocularis. Mongolian gerbils, cotton rats and… (more)

Kroeze, Wesley Kars

1987-01-01

67

Rodent repellent studies. IV. Preparation and properties of trinitrobenzene-aryl amine complexes  

USGS Publications Warehouse

Data are presented on methods of preparation, chemical arid physical characteristics, toxicity, and repellency to rodents of complexes of symmetrical trinitrohenzene with various aromatic amines: When applied in suitable carriers or incorporated in plastic .films, members of this series ofmaterials were shown to offer significant increases in time required by wild rodents to damage common packaging materials.

DeWitt, J.B.; Bellack, E.; Welch, J.F.

1953-01-01

68

A Review of the Methods of Studies on Infant Ultrasound Production and Maternal Retrieval in Small Rodents  

Microsoft Academic Search

Ultrasonic vocalizations or calls produced by young rodents have been associated with aspects of maternal behavior, in particular retrieving. We reviewed the methods of study used by investigators on each topic, focusing on intrinsic or subject variables and extrinsic or experimental variables. Intrinsic variables included the species studied, genotypes employed, number and sex composition of the litters, and the ages

Martin E. Hahn; Maria J. Lavooy

2005-01-01

69

A longitudinal study of Sin Nombre virus prevalence in rodents, southeastern Arizona.  

PubMed Central

We determined the prevalence of Sin Nombre virus antibodies in small mammals in southeastern Arizona. Of 1,234 rodents (from 13 species) captured each month from May through December 1995, only mice in the genus Peromyscus were seropositive. Antibody prevalence was 14.3% in 21 white-footed mice (P. leucopus), 13.3% in 98 brush mice (P. boylii), 0.8% in 118 cactus mice (P. eremicus), and 0% in 2 deer mice (P. maniculatus). Most antibody-positive mice were adult male Peromyscus captured close to one another early in the study. Population dynamics of brush mice suggest a correlation between population size and hantavirus-antibody prevalence. PMID:10081678

Kuenzi, A. J.; Morrison, M. L.; Swann, D. E.; Hardy, P. C.; Downard, G. T.

1999-01-01

70

Ventilatory function assessment in safety pharmacology: Optimization of rodent studies using normocapnic or hypercapnic conditions  

SciTech Connect

Although the whole body plethysmography for unrestrained animals is the most widely used method to assess the respiratory risk of new drugs in safety pharmacology, non-appropriate experimental conditions may mask deleterious side effects of some substances. If stimulant or bronchodilatory effects can be easily evidenced in rodents under standard experimental conditions, i.e. normal air breathing and diurnal phase, drug-induced respiratory depression remains more difficult to detect. This study was aimed at comparing the responsiveness of Wistar rats, Duncan Hartley guinea-pigs or BALB/c mice to the respiratory properties of theophylline (50 or 100 mg/kg p.o.) or morphine (30 mg/kg i.p.) under varying conditions (100% air versus 5% CO{sub 2}-enriched air, light versus dark day phase), in order to select the most appropriate experimental conditions to each species for safety airway investigations. Our results showed that under normocapnia the ventilatory depressant effects of morphine can be easily evidenced in mice, slightly observed in guinea-pigs and not detected in rats in any day phase. Slight hypercapnic conditions enhanced the responsiveness of rats to morphine but not that of guinea-pigs and importantly they did not blunt the airway responsiveness of rats to the stimulation and bronchodilation evoked by theophylline, the most widely used reference agent in safety pharmacology studies. In conclusion, hypercapnic conditions associated with the non-invasive whole body plethysmography should be considered for optimizing the assessment of both the ventilatory depressant potential of morphine-like substances or the respiratory stimulant effects of new drugs in the rat, the most extensively used species in rodent safety and toxicological investigations.

Goineau, Sonia; Rompion, Sonia; Guillaume, Philippe [Porsolt and Partners Pharmacology, Z.A. des Suhards, 53940 Le Genest-Saint-Isle (France); Picard, Sandra, E-mail: spicard@porsolt.co [Porsolt and Partners Pharmacology, Z.A. des Suhards, 53940 Le Genest-Saint-Isle (France)

2010-09-15

71

Comparative studies of diurnal and nocturnal rodents: differences in lifestyle result in alterations in cortical field size and number.  

PubMed

In this study we examine and describe the neuroanatomical organization of sensory cortex in four rodents: laboratory Norway rats (Long Evans; Rattus norvegicus), wild-caught Norway rats (Rattus norvegicus), wild-caught California ground squirrels (Spermophilus beecheyi), and wild-caught Eastern gray squirrels (Sciurus carolinensis). Specifically, we examined the myeloarchitecture and cytochrome oxidase reactivity for several well-identified areas in visual cortex (areas 17, 18, and 19), somatosensory cortex (areas S1, S2 and PV), and auditory cortex [areas A1+AAF (R) and TA] and compared the percentage of dorsolateral cortex devoted to each of these areas. Our results demonstrate that squirrels have a larger mean percentage of dorsolateral cortex devoted to visual areas than rats. The difference is due to the greater percentage of cortex devoted to known areas such as area 17 and area 18 and not simply to a difference in the number of visual areas, which ultimately makes this distinction even more pronounced. Furthermore, both rat groups have a larger percentage of the dorsolateral cortex devoted to somatosensory and auditory cortical areas. Differences within groups were also observed. The arboreal squirrel had a larger mean percentage of dorsolateral cortex devoted to areas 17 and 18 compared with the terrestrial squirrel. The laboratory Norway rat had a larger percentage of dorsolateral cortex devoted to both somatosensory and auditory areas than the wild-caught Norway rat. Our results indicate that differences in sensory apparatus, use of sensory systems, and niche are reflected in the organization and size of cortical areas. PMID:20886618

Campi, Katharine L; Krubitzer, Leah

2010-11-15

72

Prevalence of naturally occurring viral infections, Mycoplasma pulmonis and Clostridium piliforme in laboratory rodents in Western Europe screened from 2000 to 2003.  

PubMed

In this report prevalence rates of rodent viruses in laboratory animals are presented based on routine serological screening of mouse and rat colonies from European institutes. The prevalences found during the period 2000-2003 are compared with those reported for 1981-1984 and 1990-1993. It is shown that some infections were eliminated from laboratory animal colonies (e.g. K-virus and polyomavirus) by taking preventative measures whereas other infections such as mouse hepatitis virus and parvoviruses remained at a high rate. Further decreases in prevalence rates in the last 10 years were found for infections such as pneumonia virus of mice, reovirus type 3, Sendai virus, sialodacryoadenitis/rat coronavirus and Mycoplasma pulmonis. The introduction of new detection methods showed that mouse parvovirus and rat parvovirus, both members of the Parvoviridae family, remain a major threat to laboratory mice and rats. Guinea pig cytomegalovirus and para-influenza virus appeared to be the most prevalent agents among laboratory guinea pigs. The importance of a standardized, up-to-date screening programme is discussed. PMID:16600073

Schoondermark-van de Ven, E M E; Philipse-Bergmann, I M A; van der Logt, J T M

2006-04-01

73

Rodent phylogeny revised: analysis of six nuclear genes from all major rodent clades  

Microsoft Academic Search

BACKGROUND: Rodentia is the most diverse order of placental mammals, with extant rodent species representing about half of all placental diversity. In spite of many morphological and molecular studies, the family-level relationships among rodents and the location of the rodent root are still debated. Although various datasets have already been analyzed to solve rodent phylogeny at the family level, these

Shani Blanga-Kanfi; Hector Miranda; Osnat Penn; Tal Pupko; Ronald W DeBry; Dorothée Huchon

2009-01-01

74

Exercise, Obesity, and Cutaneous Wound Healing: Evidence from Rodent and Human Studies.  

PubMed

Significance: Impaired cutaneous wound healing is a major health concern. Obesity has been shown in a number of studies to impair wound healing, and chronic nonhealing wounds in obesity and diabetes are a major cause of limb amputations in the United States. Recent Advances: Recent evidence indicates that aberrant wound site inflammation may be an underlying cause for delayed healing. Obesity, diabetes, and other conditions such as stress and aging can result in a chronic low-level inflammatory state, thereby potentially affecting wound healing negatively. Critical Issues: Interventions which can speed the healing rate in individuals with slowly healing or nonhealing wounds are of critical importance. Recently, physical exercise training has been shown to speed healing in both aged and obese mice and in older adults. Exercise is a relatively low-cost intervention strategy which may be able to be used clinically to prevent or treat impairments in the wound-healing process. Future Directions: Little is known about the mechanisms by which exercise speeds healing. Future translational studies should address potential mechanisms for these exercise effects. Additionally, clinical studies in obese humans are necessary to determine if findings in obese rodent models translate to the human population. PMID:24761347

Pence, Brandt D; Woods, Jeffrey A

2014-01-01

75

An Experimental Approach for Selecting Appropriate Rodent Diets for Research Studies on Metabolic Disorders  

PubMed Central

Diverse high energy diets have been utilized to precipitate obesity and related metabolic disorders in rodent models, though the dietary intervention has not absolutely been standardized. The present study established usage of a customized semipurified normal control diet (NCD) and high fat diet (HFD), for research studies on diet-induced metabolic disorders in albino rats. Male Wistar rats were fed with normal pellet diet (NPD) or customized NCDs I, II, III or HFDs I, II, III for 12 weeks and parameters, namely, body weight, visceral adiposity, serum triglycerides, cholesterol, and glucose were evaluated to select an appropriate NCD and HFD. The selected HFD was further evaluated for induction of fatty liver, whilst type 2 diabetes (T2D) induction was confirmed in HFD and streptozotocin (STZ) induced diabetes model in Wistar rats. Amongst different diets tested, NCD-I and HFD-I were selected, since NCD-I exhibited close resemblance to NPD, whereas HFD-I induced metabolic alterations, particularly obesity and dyslipidemia consistently. Moreover, HFD-I elevated terminal hepatic lipids, while HFD-I/STZ treatment augmented insulin resistance index and serum glucose levels significantly indicating effective induction of fatty liver and T2D, respectively. Therefore, customized semipurified NCD-I and HFD-I can be recommended for research studies on diet-induced metabolic disorders in albino Wistar rats. PMID:24151620

Sasidharan, Suja Rani; Joseph, Joshua Allan; Anandakumar, Senthilkumar; Venkatesan, Vijayabalaji; Ariyattu Madhavan, Chandrasekharan Nair; Agarwal, Amit

2013-01-01

76

Experiment K-7-29: Connective Tissue Studies. Part 3; Rodent Tissue Repair: Skeletal Muscle  

NASA Technical Reports Server (NTRS)

Myofiber injury-repair was studied in the rat gastrocnemius following a crush injury to the lower leg prior to flight in order to understand if the regenerative responses of muscles are altered by the lack of gravitational forces during Cosmos 2044 flight. After 14 days of flight, the gastrocnemius muscle was removed from the 5 injured flight rodents and various Earth-based treatment groups for comparison. The Earth-based animals consisted of three groups of five rats with injured muscles from a simulated, tail-suspended, and vivarium as well as an uninjured basal group. The gastrocnemius muscle from each was evaluated by histochemical and immunohistochemical techniques to document myofiber, vascular, and connective tissue alterations following injury. In general the repair process was somewhat similar in all injured muscle samples with regard to extracellular matrix organization and myofiber regeneration. Small and large myofibers were present with a newly organized extracellular matrix indicative of myogenesis and muscle regeneration. In the tail-suspended animals, a more complete repair was observed with no enlarged area of non-muscle cells or matrix material visible. In contrast, the muscle samples from the flight animals were less well differentiated with more macrophages and blood vessels in the repair region but small myofibers and proteoglycans, nevertheless, were in their usual configuration. Thus, myofiber repair did vary in muscles from the different groups, but for the most part, resulted in functional muscle tissue.

Stauber, W.; Fritz, V. K.; Burkovskaya, T. E.; Ilyina-Kakueva, E. I.

1994-01-01

77

Novel Rodent Models for Macular Research  

PubMed Central

Background Many disabling human retinal disorders involve the central retina, particularly the macula. However, the commonly used rodent models in research, mouse and rat, do not possess a macula. The purpose of this study was to identify small laboratory rodents with a significant central region as potential new models for macular research. Methodology/Principal Findings Gerbillus perpallidus, Meriones unguiculatus and Phodopus campbelli, laboratory rodents less commonly used in retinal research, were subjected to confocal scanning laser ophthalmoscopy (cSLO), fluorescein and indocyanine green angiography, and spectral-domain optical coherence tomography (SD-OCT) using standard equipment (Heidelberg Engineering HRA1 and Spectralis™) adapted to small rodent eyes. The existence of a visual streak-like pattern was assessed on the basis of vascular topography, retinal thickness, and the topography of retinal ganglion cells and cone photoreceptors. All three species examined showed evidence of a significant horizontal streak-like specialization. cSLO angiography and retinal wholemounts revealed that superficial retinal blood vessels typically ramify and narrow into a sparse capillary net at the border of the respective area located dorsal to the optic nerve. Similar to the macular region, there was an absence of larger blood vessels in the streak region. Furthermore, the thickness of the photoreceptor layer and the population density of neurons in the ganglion cell layer were markedly increased in the visual streak region. Conclusions/Significance The retinal specializations of Gerbillus perpallidus, Meriones unguiculatus and Phodopus campbelli resemble features of the primate macula. Hence, the rodents reported here may serve to study aspects of macular development and diseases like age-related macular degeneration and diabetic macular edema, and the preclinical assessment of therapeutic strategies. PMID:20976212

Huber, Gesine; Heynen, Severin; Imsand, Coni; vom Hagen, Franziska; Muehlfriedel, Regine; Tanimoto, Naoyuki; Feng, Yuxi; Hammes, Hans-Peter; Grimm, Christian; Peichl, Leo; Seeliger, Mathias W.; Beck, Susanne C.

2010-01-01

78

Wentworth Institute Mechanical Engineering Laboratory Manual. Laboratory Study Guide.  

ERIC Educational Resources Information Center

This publication is a laboratory study guide designed for mechanical engineering students. All of the experiments (with the exception of experiment No. 1) contained in the Mechanical Engineering Laboratory Manual have been included in this guide. Brief theoretical backgrounds, examples and their solutions, charts, graphs, illustrations, and…

Avakian, Harry; And Others

79

Need for dietary control by caloric restriction in rodent toxicology and carcinogenicity studies  

Microsoft Academic Search

The conditions under which laboratory animals are maintained can powerfully influence the results of toxicological studies utilized for risk assessment. Nutrition is of importance in toxicological bioassays and research, because diet composition and the conditions under which it is fed can affect the metabolism and activity of xenobiotic test substances and alter the results and reproducibility of long?term studies. It

Kevin P. Keenan; Philippe Laroque; Rakesh Dixit

1998-01-01

80

Tactile and non-tactile sensory paradigms for fMRI and neurophysiologic studies in rodents  

PubMed Central

Functional magnetic resonance imaging (fMRI) has become a popular functional imaging tool for human studies. Future diagnostic use of fMRI depends, however, on a suitable neurophysiologic interpretation of the blood oxygenation level dependent (BOLD) signal change. This particular goal is best achieved in animal models primarily due to the invasive nature of other methods used and/or pharmacological agents applied to probe different nuances of neuronal (and glial) activity coupled to the BOLD signal change. In the last decade, we have directed our efforts towards the development of stimulation protocols for a variety of modalities in rodents with fMRI. Perception of the natural world relies on the formation of multi-dimensional representation of stimuli impinging on the different sensory systems, leading to the hypothesis that a sensory stimulus may have very different neurophysiologic outcome(s) when paired with a near simultaneous event in another modality. Before approaching this level of complexity, reliable measures must be obtained of the relatively small changes in the BOLD signal and other neurophysiologic markers (electrical, blood flow) induced by different peripheral stimuli. Here we describe different tactile (i.e., forepaw, whisker) and non-tactile (i.e., olfactory, visual) sensory paradigms applied to the anesthetized rat. The main focus is on development and validation of methods for reproducible stimulation of each sensory modality applied independently or in conjunction with one another, both inside and outside the magnet. We discuss similarities and/or differences across the sensory systems as well as advantages they may have for studying essential neuroscientific questions. We envisage that the different sensory paradigms described here may be applied directly to studies of multi-sensory interactions in anesthetized rats, en route to a rudimentary understanding of the awake functioning brain where various sensory cues presumably interrelate. PMID:18839094

Sanganahalli, Basavaraju G.; Bailey, Christopher J.; Herman, Peter; Hyder, Fahmeed

2013-01-01

81

CAVEATS REGARDING THE USE OF THE LABORATORY RATS AS A MODEL FOR ACUTE TOXICOLOGICAL STUDIES: MODULATION OF THE TOXIC RESPONSE VIA PHYSIOLOGICAL AND BEHAVIORAL MECHANISMS  

EPA Science Inventory

The rodent, specifically the inbred laboratory rat, is the primary experimental animal used in toxicology testing. Despite its popularity, recent studies from our laboratory and others raise a number of questions concerning the rat's appropriateness as an animal model for toxicol...

82

Imaging Neuronal Populations in Behaving Rodents: Paradigms for Studying Neural Circuits Underlying Behavior in the Mammalian Cortex  

PubMed Central

Understanding the neural correlates of behavior in the mammalian cortex requires measurements of activity in awake, behaving animals. Rodents have emerged as a powerful model for dissecting the cortical circuits underlying behavior attributable to the convergence of several methods. Genetically encoded calcium indicators combined with viral-mediated or transgenic tools enable chronic monitoring of calcium signals in neuronal populations and subcellular structures of identified cell types. Stable one- and two-photon imaging of neuronal activity in awake, behaving animals is now possible using new behavioral paradigms in head-fixed animals, or using novel miniature head-mounted microscopes in freely moving animals. This mini-symposium will highlight recent applications of these methods for studying sensorimotor integration, decision making, learning, and memory in cortical and subcortical brain areas. We will outline future prospects and challenges for identifying the neural underpinnings of task-dependent behavior using cellular imaging in rodents. PMID:24198355

Andermann, Mark L.; Keck, Tara; Xu, Ning-Long; Ziv, Yaniv

2013-01-01

83

Dynamic Causal Models and Physiological Inference: A Validation Study Using Isoflurane Anaesthesia in Rodents  

PubMed Central

Generative models of neuroimaging and electrophysiological data present new opportunities for accessing hidden or latent brain states. Dynamic causal modeling (DCM) uses Bayesian model inversion and selection to infer the synaptic mechanisms underlying empirically observed brain responses. DCM for electrophysiological data, in particular, aims to estimate the relative strength of synaptic transmission at different cell types and via specific neurotransmitters. Here, we report a DCM validation study concerning inference on excitatory and inhibitory synaptic transmission, using different doses of a volatile anaesthetic agent (isoflurane) to parametrically modify excitatory and inhibitory synaptic processing while recording local field potentials (LFPs) from primary auditory cortex (A1) and the posterior auditory field (PAF) in the auditory belt region in rodents. We test whether DCM can infer, from the LFP measurements, the expected drug-induced changes in synaptic transmission mediated via fast ionotropic receptors; i.e., excitatory (glutamatergic) AMPA and inhibitory GABAA receptors. Cross- and auto-spectra from the two regions were used to optimise three DCMs based on biologically plausible neural mass models and specific network architectures. Consistent with known extrinsic connectivity patterns in sensory hierarchies, we found that a model comprising forward connections from A1 to PAF and backward connections from PAF to A1 outperformed a model with forward connections from PAF to A1 and backward connections from A1 to PAF and a model with reciprocal lateral connections. The parameter estimates from the most plausible model indicated that the amplitude of fast glutamatergic excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) behaved as predicted by previous neurophysiological studies. Specifically, with increasing levels of anaesthesia, glutamatergic EPSPs decreased linearly, whereas fast GABAergic IPSPs displayed a nonlinear (saturating) increase. The consistency of our model-based in vivo results with experimental in vitro results lends further validity to the capacity of DCM to infer on synaptic processes using macroscopic neurophysiological data. PMID:21829652

Moran, Rosalyn J.; Jung, Fabienne; Kumagai, Tetsuya; Endepols, Heike; Graf, Rudolf; Dolan, Raymond J.; Friston, Karl J.; Stephan, Klaas E.; Tittgemeyer, Marc

2011-01-01

84

Linking human behavior to environmental effects using a case study of urban rodent control  

EPA Science Inventory

Pest control is common practice in many land use activities worldwide. Although often inadvertent, pest control can affect non-target species, sometimes fatally. Using social survey data about residential rodent control behavior in two areas in California, we applied a framewor...

85

Rodent-repellent studies. I. Method for the evaluation of chemical repellents  

USGS Publications Warehouse

A biological assay procedure and a method for the numerical expression of results have been devised for the determination of the repellency to rodents of different chemical compounds. The procedure is based upon the degree of acceptability of foods containing the candidate repellents,. and has been shown. to offer a rapid, reliable measure of repellent activIty.

Bellack, E.; DeWitt, J.B.

1949-01-01

86

Transgenic Rodent Models to Study Alpha-Synuclein Pathogenesis, with a Focus on Cognitive Deficits.  

PubMed

The aggregation of alpha-synuclein (aSyn) has been implicated in a number of degenerative diseases collectively termed synucleinopathies. Although most cases of synucleinopathies are idiopathic in nature, there are familial cases of these diseases that are due to mutations or multiplications of the gene coding for aSyn. Two of the most common synucleinopathies are Parkinson's diseaseParkinson's disease (PD) and dementiaDementia with Lewy bodies (DLB). Both of these diseases present with cognitive deficits, though with different clinical and temporal features. In PD, cognitive deficits are subtle, may occur before the onset of the classical motor symptoms, and only occasionally lead to dementiaDementia in the later stages of the disease. In contrast, dementiaDementia is the dominating feature of DLB from the disease onset. The impact of aSyn pathology on the development of neurobiological and behavioralBehavioral impairments can be investigated using rodent models. There are currently several lines of transgenic mice overexpressing wild-type or mutated aSyn under various promoters. This review will provide an updated synopsis of the mouseMouse lines available, summarize their cognitive deficits, and reflect on how deficits observed in these mice relate to the disease process in humans. In addition, we will review mouseMouse lines where knockout strategies have been applied to study the effects of aSyn on various cognitive tasks and comment on how these lines have been used in combination with other transgenic strains, or with human aSyn overexpression by viral vectors. Finally, we will discuss the recent advent of bacterial artificial chromosome (BAC) transgenic models of PD and their effectiveness in modeling cognitive decline in PD. PMID:25218491

Hatami, Asa; Chesselet, Marie-Francoise

2014-09-14

87

Evaluation of NASA Foodbars as a Standard Diet for Use in Short-Term Rodent Space Flight Studies  

NASA Technical Reports Server (NTRS)

A standard rodent diet for space flight must meet the unique conditions imposed by the space environment and must be nutritionally adequate since diet can influence the outcome of experiments. This paper evaluates the use of National Aeronautics and Space Administration (NASA) developed Foodbars as a standard space flight diet for rats. The Foodbar's semi-purified formulation permits criteria such as nutrient consistency, high nutrient bioavailability and flexibility of formulation to be met. Extrusion of the semi-purified diet produces Foodbars with the proper texture and a non-crumbing solid form for use in space. Treatment of Foodbar with 0.1% potassium sorbate prevents mold growth. Irradiation (15-25 kGy) prevents bacterial growth and in combination with sorbate-treatment provides added protection against mold for shelf-stability. However, during the development process, nutrient analyses indicated that extrusion and irradiation produced nutrient losses. Nutrients were adjusted accordingly to compensate for processing losses. Nutrient analysis of Foodbars continues to be performed routinely to monitor nutrient levels. It is important that the standard rodent diet provide nutrients that will prevent deficiency but also avoid excess that may mask physiological changes produced by space flight. All vitamins levels in the Foodbars, except for vitamin K conformed to or exceeded the current NRC (1995) recommendations. All indispensable amino acids in Foodbar conformed to or exceeded the NRC nutrient recommendation for mice growth and rat maintenance. However, some indispensable amino acids were slightly below recommendations for rat reproduction/growth. Short-term (18-20 d) animal feeding studies indicated that Foodbars were palatable, supported growth and maintained health in rats. Results indicated that NASA rodent Foodbars meet both the physical and nutritional criteria required to support rodents in the space environment and thus, may be used successfully as a standard diet for short-term space flight studies. However, nutritional adequacy of NASA Rodent Foodbars as a standard diet on longer duration (>20 d) space flight missions remains to be determined.

Tou, Janet; Grindeland, Richard; Barrett, Joyce; Dalton, Bonnie; Mandel, Adrian; Wade, Charles

2003-01-01

88

The Use of Cystometry in Small Rodents: A Study of Bladder Chemosensation  

PubMed Central

The lower urinary tract (LUT) functions as a dynamic reservoir that is able to store urine and to efficiently expel it at a convenient time. While storing urine, however, the bladder is exposed for prolonged periods to waste products. By acting as a tight barrier, the epithelial lining of the LUT, the urothelium, avoids re-absorption of harmful substances. Moreover, noxious chemicals stimulate the bladder's nociceptive innervation and initiate voiding contractions that expel the bladder's contents. Interestingly, the bladder's sensitivity to noxious chemicals has been used successfully in clinical practice, by intravesically infusing the TRPV1 agonist capsaicin to treat neurogenic bladder overactivity1. This underscores the advantage of viewing the bladder as a chemosensory organ and prompts for further clinical research. However, ethical issues severely limit the possibilities to perform, in human subjects, the invasive measurements that are necessary to unravel the molecular bases of LUT clinical pharmacology. A way to overcome this limitation is the use of several animal models2. Here we describe the implementation of cystometry in mice and rats, a technique that allows measuring the intravesical pressure in conditions of controlled bladder perfusion. After laparotomy, a catheter is implanted in the bladder dome and tunneled subcutaneously to the interscapular region. Then the bladder can be filled at a controlled rate, while the urethra is left free for micturition. During the repetitive cycles of filling and voiding, intravesical pressure can be measured via the implanted catheter. As such, the pressure changes can be quantified and analyzed. Moreover, simultaneous measurement of the voided volume allows distinguishing voiding contractions from non-voiding contractions3. Importantly, due to the differences in micturition control between rodents and humans, cystometric measurements in these animals have only limited translational value4. Nevertheless, they are quite instrumental in the study of bladder pathophysiology and pharmacology in experimental pre-clinical settings. Recent research using this technique has revealed the key role of novel molecular players in the mechano- and chemo-sensory properties of the bladder. PMID:22929055

Uvin, Pieter; Everaerts, Wouter; Pinto, Silvia; Alpízar, Yeranddy A.; Boudes, Mathieu; Gevaert, Thomas; Voets, Thomas; Nilius, Bernd; Talavera, Karel; De Ridder, Dirk

2012-01-01

89

The Estrogenic Content of Rodent Diets, Bedding, Cages, and Water Bottles and Its Effect on Bisphenol A Studies  

PubMed Central

The lowest observed adverse effect level for bisphenol A (BPA) in mice and rats is currently poorly defined due to inconsistent study designs and results in published studies. The objectives of the current study were to (1) compare the estrogenic content of rodent diets, bedding, cages, and water bottles to evaluate their impact on the estrogenic activity of BPA and (2) review the literature on BPA to determine the most frequently reported diets, beddings, cages, and water bottles used in animal studies. Our literature review indicated that low-dose BPA animal studies have inconsistent results and that factors contributing to this inconsistency are the uses of high-phytoestrogen diets and the different routes of exposure. In 44% (76 of 172) of all reports, rodents were exposed to BPA via the subcutaneous route. Our literature review further indicated that the type of diet, bedding, caging, and water bottles used in BPA studies were not always reported. Only 37% (64 of 172) of the reports described the diet used. In light of these findings, we recommend the use of a diet containing low levels of phytoestrogen (less than 20 µg/g diet) and metabolizable energy (approximately 3.1 kcal/g diet) and estrogen-free bedding, cages, and water bottles for studies evaluating the estrogenic activity of endocrine-disrupting compounds such as BPA. The oral route of BPA exposure should be used when results are to be extrapolated to humans. PMID:23562095

Thigpen, Julius E; Setchell, Kenneth DR; Kissling, Grace E; Locklear, Jacqueline; Caviness, Gordon F; Whiteside, Tanya; Belcher, Scott M; Brown, Nadine M; Collins, Bradley J; Lih, Fred B; Tomer, Kenneth B; Padilla-Banks, Elizabeth; Camacho, Luísa; Adsit, Floyd G; Grant, Mary

2013-01-01

90

Variability of selected nutrients and contaminants monitored in rodent diets: A 6-year study  

SciTech Connect

The results are given from monitoring a commercial closed-formula cereal-based rodent diet (Purina 5010), two open-formula cereal-based diets (NIH-31 and NIH-07), and one purified diet (AIN-76) for selected nutrients and contaminants. The observed concentrations of nutrients (protein, fat, vitamin A, and thiamine) approximated the manufacturer specifications for closed-formula cereal diet, while the average concentrations of nutrients found in the open-formula cereal diets were well above the nominal concentrations. Nominal concentrations for these open-formula diets tended to be close to the minimum values that were observed. Except for protein levels, greater variation in nutrient concentrations was found in the purified diet than in the cereal diets. Contaminants were generally much lower in the purified diet than in the cereal diets, but the variation of contaminants was about equal in the two types of diets. Open- and closed-formula cereal diets appear to be very similar to each other in the degree of variation of nutrients and contaminants. Cadmium, lead, and selenium are the constituents of greatest concern in assuring the quality of the rodent diets that were evaluated.

Oller, W.L.; Kendall, D.C.; Greenman, D.L. (National Center for Toxicological Research, Jefferson, AR (USA))

1989-01-01

91

Chemicals associated with site-specific neoplasia in 1394 long-term carcinogenesis experiments in laboratory rodents.  

PubMed Central

The carcinogenicity data base used for this paper originated in the late 1960s by the National Cancer Institute and since 1978 has been continued and made more comprehensive by the National Toxicology Program. The extensive files contain among other sets of information detailed pathology data on more than 400 long-term (most often 24 month) chemical carcinogenesis studies, comprised of nearly 1600 individual experiments having at least 10 million tissue sections that have been evaluated for toxicity and carcinogenicity. Using the current data set of 379 studies made up of 1394 experiments, we have compiled listings of chemicals having like carcinogenic target sites for each of the 34 organs or systems for which histopathology diagnoses have been recorded routinely. The most common tumor site is the liver (15% of all experiments), followed in rank order by: lung, hematopoietic system and kidneys, mammary glands, forestomach, thyroid glands, Zymbal glands, urinary bladder, skin and uterus/cervix, and circulatory system and adrenal glands. These compilations are most useful for maintaining a historic perspective when evaluating the carcinogenicity of contemporary experiments. Equally important, the chemical-tumor-organ connection permits an evaluation of how well chemically induced cancers in a particular organ in one sex or species will predict or correlate with the other sex or species. Using liver cancers as an example, the overall interspecies concordance is 80%. Likewise target site predictions can be made for chemicals selected for study that may be similar to those already evaluated; thereby experimental protocols could be adjusted to allow, for example, more extensive pathology on preselected target organs (i.e., serial sections of the kidney). Further from these observations, one could decide to use two strains of mice to evaluate a short-chain chlorinated aliphatic compound or to study a human carcinogen in a sex-species known to develop chemically induced tumors in the same site observed in humans. Structural classes of chemicals having a propensity for certain organs can be easily identified from these data. Sex-species responders to particular induced cancers become clearly evident, such as in the ovary of female mice or in the kidney of male rats. PMID:1773796

Huff, J; Cirvello, J; Haseman, J; Bucher, J

1991-01-01

92

The allometry of rodent intestines  

Microsoft Academic Search

This study examined the allometry of the small intestine, caecum, colon and large intestine of rodents (n = 51) using a phylogenetically informed approach. Strong phylogenetic signal was detected in the data for the caecum, colon\\u000a and large intestine, but not for the small intestine. Most of the phylogenetic signal could be attributed to clade effects\\u000a associated with herbivorous versus omnivorous rodents.

Barry G. Lovegrove

2010-01-01

93

Evaluation of three feed-through insecticides using two rodent and two sand fly species as models.  

PubMed

The efficacy of 3 rodent feed-through insecticides (novaluron, pyriproxyfen, and ivermectin) was determined against larvae of the sand flies Phlebotomus duboscqi and P. papatasi using Syrian hamsters (Mesocricetus auratus) and Mongolian gerbils (Meriones unguiculatus) as laboratory models. For each insecticide, there were no significant differences between the longevity or percentage survival of sand fly larvae that had been fed feces of treated rodents for each sand fly or rodent species pairing. The results of this study suggest that larvae of P. duboscqi and P. papatasi are equally susceptible to the concentrations of the rodent feed-through insecticides tested in this study and that these insecticides are pharmacologically compatible with different rodent/sand fly interactions. PMID:23833909

Mascari, T M; Stout, R W; Foil, L D

2012-09-01

94

Rodent models of glaucoma  

PubMed Central

Glaucoma is a progressive, age-related optic neuropathy and a leading cause of irreversible blindness in the world. Animal models of glaucoma are essential to our continued efforts of elucidating the natural course of the disease and to developing therapeutic interventions to halt or reverse the progression of the condition. Over the past 10–15 years, rodents have become a popular model organism in which to study glaucoma, because of their high degree of availability, relatively low cost, short life-span, and amenability to experimental and genetic manipulation. In this review, we examine the numerous in vivo and in vitro rodent models of glaucoma, discuss the methods used to generate them, summarize some of the major findings obtained in these models, and identify individual strengths and weaknesses for the various systems. PMID:19379796

Johnson, Thomas V.; Tomarev, Stanislav I.

2010-01-01

95

Water Sciences Laboratory Completes Creighton Groundwater Study  

E-print Network

Water Sciences Laboratory Completes Creighton Groundwater Study Faculty and staff from the Water Sciences Laboratory (WSL) at the University of Nebraska- Lincoln completed a groundwater research project groundwater nitrate contamination were discussed and Spalding and Burbach offered several courses of action

Nebraska-Lincoln, University of

96

New Building, Old Parasite: Mesostigmatid Mites—An Ever-Present Threat to Barrier Rodent Facilities  

Microsoft Academic Search

Mesostigmatid mites are blood-sucking parasitic mites found in wild rodent populations. Periodically they can also become a problem for laboratory rodent colonies, particu- larly when building construction or renovations disturb colonies of commensal (building) rodents that had been act- ing as hosts. Mesostigmatid mites infest both rats and mice and, unlike the more common rodent fur mites (Myobia, Myocoptes, and

Julie Watson

97

LABORATORY SCALE STEAM INJECTION TREATABILITY STUDIES  

EPA Science Inventory

Laboratory scale steam injection treatability studies were first developed at The University of California-Berkeley. A comparable testing facility has been developed at USEPA's Robert S. Kerr Environmental Research Center. Experience has already shown that many volatile organic...

98

Radiogenic Isotope Laboratory: Provenance Studies  

NSDL National Science Digital Library

This site showcases two research projects at the University of Wisconsin that are using radiogenic isotopes to study sediment provenance. One research group is studying large-scale terrane translation along western North America, and the other is looking at tectonics, provenance, and paleoclimate in Wyoming's Green River Basin. The site provides a project description and selected publications for each research focus. Some publications are available as PDF's.

Laboratory, Department O.; Wisconsin, University O.

99

Psychopharmacological study of agmatine in behavioral tests of schizophrenia in rodents.  

PubMed

The effect of agmatine in preclinical behavioral tests of schizophrenia has been examined in rodents. Agmatine at the doses of 40 and 80 mg/kg blocked conditioned avoidance responding, attenuated apomorphine induced climbing, diminished amphetamine and ketamine hyperlocomotor activity and augmented plasma prolactin levels. Pretreatment of animals with 20 mg/kg of agmatine potentiated the inhibitory effect of haloperidol (0.1 mg/kg, ip) and olanzepine (0.5 mg/kg, ip) in conditioned avoidance response test and apomorphine induced climbing. Agmatine alone at the doses tested here did not induce any cataleptic behavior in mice. However significant catalepsy was exhibited when agmatine (80 mg/kg, ip) was injected to mice pretreated with 5-HT1A receptor antagonist, WAY100, 635. These results indicate that agmatine via regulation of brain dopaminergic signaling modulates dopamine mediated behaviors. The alteration in the levels of endogenous agmatine may contribute to the genesis of psychosis and development of drugs that enhance endogenous agmatine content may be better therapeutic approach to treat schizophrenia with low incidences of extra pyramidal side effects. PMID:21989253

Kotagale, Nandkishor R; Taksande, Brijesh G; Wadhwani, Paresh J; Palhade, Mahesh W; Mendhi, Sachin M; Gawande, Dinesh Y; Hadole, Pravin N; Chopde, Chandrabhan T

2012-01-01

100

Non-invasive muscle contraction assay to study rodent models of sarcopenia  

PubMed Central

Background Age-related sarcopenia is a disease state of loss of muscle mass and strength that affects physical function and mobility leading to falls, fractures, and disability. The need for therapies to treat age-related sarcopenia has attracted intensive preclinical research. To facilitate the discovery of these therapies, we have developed a non-invasive rat muscle functional assay system to efficiently measure muscle force and evaluate the efficacy of drug candidates. Methods The lower leg muscles of anesthetized rats are artificially stimulated with surface electrodes on the knee holders and the heel support, causing the lower leg muscles to push isometric pedals that are attached to force transducers. We developed a stimulation protocol to perform a fatigability test that reveals functional muscle parameters like maximal force, the rate of fatigue, fatigue-resistant force, as well as a fatigable muscle force index. The system is evaluated in a rat aging model and a rat glucocorticoid-induced muscle loss model Results The aged rats were generally weaker than adult rats and showed a greater reduction in their fatigable force when compared to their fatigue-resistant force. Glucocorticoid treated rats mostly lost fatigable force and fatigued at a higher rate, indicating reduced force from glycolytic fibers with reduced energy reserves. Conclusions The involuntary contraction assay is a reliable system to assess muscle function in rodents and can be applied in preclinical research, including age-related sarcopenia and other myopathy. PMID:22035016

2011-01-01

101

Laboratory Studies of DIB Carriers  

NASA Technical Reports Server (NTRS)

Spectroscopic studies of the following potential diffuse interstellar band (DIB) carriers are reviewed: unspecified organics, carbon chains, polycyclic aromatic hydrocarbons (PAHs), fullerenes and derivatives, as well as porphyrins and related material. An assessment of each is given, along with suggestions for further experimental studies needed to fully test each candidate. Of the experimental techniques in common use matrix isolation spectroscopy with neon matrices is the most appropriate for the DIBs. The low vapor pressure and high reactivity of these materials preclude gas phase studies on many of these species. At this point, given the type and quality of published data available, carbon chains and PARs are the most promising candidates for a number of the DIBs.

Allamandola, L. J.

1995-01-01

102

Two-photon microscopy as a tool to study blood flow and neurovascular coupling in the rodent brain  

PubMed Central

The cerebral vascular system services the constant demand for energy during neuronal activity in the brain. Attempts to delineate the logic of neurovascular coupling have been greatly aided by the advent of two-photon laser scanning microscopy to image both blood flow and the activity of individual cells below the surface of the brain. Here we provide a technical guide to imaging cerebral blood flow in rodents. We describe in detail the surgical procedures required to generate cranial windows for optical access to the cortex of both rats and mice and the use of two-photon microscopy to accurately measure blood flow in individual cortical vessels concurrent with local cellular activity. We further provide examples on how these techniques can be applied to the study of local blood flow regulation and vascular pathologies such as small-scale stroke. PMID:22293983

Shih, Andy Y; Driscoll, Jonathan D; Drew, Patrick J; Nishimura, Nozomi; Schaffer, Chris B; Kleinfeld, David

2012-01-01

103

Echocardiographic characterization of the cardiovascular phenotype in rodent models.  

PubMed

Echocardiographic techniques are commonly utilized to describe the rodent cardiovascular phenotype. These approaches are contrasted with other in vivo methods and are positioned in the assay selection process by a review of studies from our laboratory and others. Although not conventionally considered a biomarker, the technique has the potential to be exploited as a marker of intentional or unanticipated toxic biological effects in the preclinical development of drugs and chemicals. PMID:16507551

Hoit, Brian D

2006-01-01

104

Vasovagal Syncope Case Study/Laboratory Supplement  

NSDL National Science Digital Library

This is a case study emphasizing neural control of the cardiovascular system. This study was designed to be completed during an undergraduate anatomy and physiology laboratory period on the study of blood pressure and hemodynamics. This case study involves guided student exploration in understanding of the autonomic nervous system, heart rate, total peripheral resistance, cardiac output, blood pressure, and autoregulatory range. This study also includes an optional section on cardiovascular responses in pregnancy.

PhD Jan Foster (North Greenville University Biology)

2012-05-01

105

Spatial Segregation between Invasive and Native Commensal Rodents in an Urban Environment: A Case Study in Niamey, Niger  

PubMed Central

Invasive rodents have been responsible for the diffusion worldwide of many zoonotic agents, thus representing major threats for public health. Cities are important hubs for people and goods exchange and are thus expected to play a pivotal role in invasive commensal rodent dissemination. Yet, data about urban rodents' ecology, especially invasive vs. native species interactions, are dramatically scarce. Here, we provide results of an extensive survey of urban rodents conducted in Niamey, Niger, depicting the early stages of rodent bioinvasions within a city. We explore the species-specific spatial distributions throughout the city using contrasted approaches, namely field sampling, co-occurrence analysis, occupancy modelling and indicator geostatistics. We show that (i) two species (i.e. rural-like vs. truly commensal) assemblages can be identified, and that (ii) within commensal rodents, invasive (Rattus rattus and Mus musculus) and native (Mastomys natalensis) species are spatially segregated. Moreover, several pieces of arguments tend to suggest that these exclusive distributions reflect an ongoing native-to-invasive species turn over. The underlying processes as well as the possible consequences for humans are discussed. PMID:25379785

Garba, Madougou; Dalecky, Ambroise; Kadaoure, Ibrahima; Kane, Mamadou; Hima, Karmadine; Veran, Sophie; Gagare, Sama; Gauthier, Philippe; Tatard, Caroline; Rossi, Jean-Pierre; Dobigny, Gauthier

2014-01-01

106

Spatial segregation between invasive and native commensal rodents in an urban environment: a case study in Niamey, Niger.  

PubMed

Invasive rodents have been responsible for the diffusion worldwide of many zoonotic agents, thus representing major threats for public health. Cities are important hubs for people and goods exchange and are thus expected to play a pivotal role in invasive commensal rodent dissemination. Yet, data about urban rodents' ecology, especially invasive vs. native species interactions, are dramatically scarce. Here, we provide results of an extensive survey of urban rodents conducted in Niamey, Niger, depicting the early stages of rodent bioinvasions within a city. We explore the species-specific spatial distributions throughout the city using contrasted approaches, namely field sampling, co-occurrence analysis, occupancy modelling and indicator geostatistics. We show that (i) two species (i.e. rural-like vs. truly commensal) assemblages can be identified, and that (ii) within commensal rodents, invasive (Rattus rattus and Mus musculus) and native (Mastomys natalensis) species are spatially segregated. Moreover, several pieces of arguments tend to suggest that these exclusive distributions reflect an ongoing native-to-invasive species turn over. The underlying processes as well as the possible consequences for humans are discussed. PMID:25379785

Garba, Madougou; Dalecky, Ambroise; Kadaoure, Ibrahima; Kane, Mamadou; Hima, Karmadine; Veran, Sophie; Gagare, Sama; Gauthier, Philippe; Tatard, Caroline; Rossi, Jean-Pierre; Dobigny, Gauthier

2014-01-01

107

STUDY OF THE PREVALENCE OF Capillaria hepatica IN HUMANS AND RODENTS IN AN URBAN AREA OF THE CITY OF PORTO VELHO, RONDÔNIA, BRAZIL  

PubMed Central

Introduction: Hepatic capillariosis, caused by Capillaria hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. Methods: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. Results: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. Conclusions: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower. PMID:25651325

da Rocha, Elierson José Gomes; Basano, Sérgio de Almeida; de Souza, Márcia Maria; Honda, Eduardo Resende; de Castro, Márcio Botelho; Colodel, Edson Moleta; Silva, Jéssica Carolinne Damasceno e; Barros, Lauro Prado; Rodrigues, Elisa Sousa; Camargo, Luís Marcelo Aranha

2015-01-01

108

Rodent-Vegetation Relationships in Southeastern Montana  

Microsoft Academic Search

Plant communities of southeastern Montana were surveyed for rodents over a two year period. Deer mice (Peromyscus maniculatus) were the most abundant rodent species found on the study area. Prairie voles (Microtus ochrogaster), meadow voles (M. pennsylvanicus), sagebrush voles (Lagurus curtatus), Wyoming pocket mice (Perognathus fasciatus), thirteen-lined ground squirrels (Spermophilus tridecemlineatus), least chipmunks (Eutamias minimus), and eastern fox squirrels (Sciurus

Daniel W. Uresk; Richard M. Hansen

109

Seasonal selectivity of Magellanic horned owl ( Bubo magellanicus ) on rodents  

Microsoft Academic Search

This study examines prey selection by Magellanic horned owls (Bubo magellanicus) in an ecotonal steppe area of northwestern Argentine Patagonia, and analyzes morphological and behavioral traits of the owls’ main rodent prey. The owl’s diet was studied for two years, along with field estimates of rodent abundance. The frequency distribution of rodents was significantly different from that estimated from trapping,

Ana Trejo; Nadia Guthmann; Mariana Lozada

2005-01-01

110

RADIATION ECOLOGY ISSUES ASSOCIATED WITH MURINE RODENTS AND SHREWS IN THE CHERNOBYL EXCLUSION ZONE  

Microsoft Academic Search

This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals, and reviews interspecies differences in radionuclide accumulations and factors affecting the radionuclide accumulations. It is shown that bioavailability of

E. Farfan; T. Jannik

2011-01-01

111

Robertsonian fusions, pericentromeric repeat organization and evolution: a case study within a highly polymorphic rodent species, Gerbillus nigeriae.  

PubMed

Pericentromeric repeats have been claimed to mediate centric fusions through heterologous recombination of arrays of tandemly repeated and highly homogenized motifs. However, mammalian case studies are essentially restricted to pathologic fusions in human, or to the house mouse Roberstonian (Rb) races. We here provide an example in a wild gerbil rodent, Gerbillus nigeriae, which displays an extensive Rb polymorphism, with 2n ranging between 2n = 60 and 74. The distribution of two closely related repeats, GERB1 and GERB2 that were previously isolated by Volobouev et al. (Chromosoma 104:252-259, 1995) in this African species, were investigated in the genomes of seven individuals with various diploid numbers. Our results clearly show that GERB1 and GERB2 are organized in a non-random manner, with GERB2 and GERB1 being clearly juxtacentromeric and centromeric, respectively. Finally, cloning and sequencing revealed that, unlike GERB2, GERB1 monomers display a more homogeneous organization at both the nucleotide and structural levels. Altogether, our results point toward a pivotal role of GERB1 repeats in the mediation of Rb fusions through heterologous recombination, with some evidence of subsequent loss of repeats after the Rb fusion during the course of evolution of metacentric elements. Moreover, the repeat pattern observed in G. nigeriae closely matches the organization and sequence structure of satellite DNAs described in human acrocentrics. Consequently, G. nigeriae appears as an additional model for the study of repeat evolution and its role in centric fusions and their consequences in mammals. PMID:20361248

Gauthier, Philippe; Hima, Karmadine; Dobigny, Gauthier

2010-06-01

112

Characterization of human and rodent native and recombinant adenosine A(2B) receptors by radioligand binding studies.  

PubMed

Adenosine A(2B) receptors of native human and rodent cell lines were investigated using [(3)H]PSB-298 [(8-{4-[2-(2-hydroxyethylamino)-2-oxoethoxy]phenyl}-1-propylxanthine] in radioligand binding studies. [(3)H]PSB-298 showed saturable and reversible binding. It exhibited a K(D) value of 60 +/- 1 nM and limited capacity (B(max) = 3.511 fmol per milligram protein) at recombinant human adenosine A(2B) receptors expressed in human embryonic kidney cells (HEK-293). The addition of sodium chloride (100 mM) led to a threefold increase in the number of binding sites recognized by the radioligand. The curve of the agonist 5'-N-ethylcarboxamidoadenosine (NECA) was shifted to the right in the presence of NaCl, while the curve of the antagonist PSB-298 was shifted to the left, indicating that PSB-298 may be an inverse agonist at A(2B) receptors. Adenosine A(2B) receptors were shown to be the major adenosine A(2) receptor subtype on the mouse neuroblastoma x rat glioma hybrid cell line NG108-15 cells. Binding studies at rat INS-1 cells (insulin secreting cell line) demonstrated that [(3)H]PSB-298 is a selective radioligand for adenosine A(2B) binding sites in this cell line. PMID:18404493

Bertarelli, Daniela C G; Diekmann, Martina; Hayallah, Alaa M; Rüsing, Dorothee; Iqbal, Jamshed; Preiss, Birgit; Verspohl, Eugen J; Müller, Christa E

2006-09-01

113

Preparation and biodistribution studies of a radiogallium-acetylacetonate bis (thiosemicarbazone) complex in tumor-bearing rodents.  

PubMed

Various radiometal complexes have been developed for tumor imaging, especially Ga-68 tracer. In the present study, the development of a radiogallium bis-thiosemicarbazone complex has been reported. [(67)Ga] acetylacetonate bis(thiosemicarbazone) complex ([(67)Ga] AATS) was prepared starting [(67)Ga]Gallium acetate and freshly prepared acetylacetonate bis (thiosemicarbazone) (AATS) in 30 min at 90°C. The partition co-efficient and the stability of the tracer were determined in final solution (25°C) and the presence of human serum (37°C) up to 24 h. The biodistribution of the labeled compound in wild-type and fibrosarcoma-bearing rodents were determined up to 72 h. The radiolabled Ga complex was prepared in high radiochemical purity (> 97%, HPLC) followed by initial biodistribution data with the significant tumor accumulation of the tracer in 2 h which is far higher than free Ga-67 cation while the compound wash-out is significantly faster. Above-mentioned pharmacokinetic properties suggest an interesting radiogallium complex while prepared by the PET Ga radioisotope, (68)Ga, in accordance with the physical half life, for use in fibrosarcoma tumors, and possibly other malignancies. PMID:24250475

Jalilian, Amir Reza; Yousefnia, Hassan; Shafaii, Kamaleddin; Novinrouz, Aytak; Rajamand, Amir Abbas

2012-01-01

114

Laboratory microfusion capability study. Phase II report  

SciTech Connect

The purpose of this study is to elucidate the issues involved in developing a Laboratory Microfusion Capability (LMC) which is the major objective of the Inertial Confinement Fusion (ICF) program within the purview of the Department of Energy`s Defense Programs. The study was initiated to support a number of DOE management needs: to provide insight for the evolution of the ICF program; to afford guidance to the ICF laboratories in planning their research and development programs; to inform Congress and others of the details and implications of the LMC; to identify criteria for selection of a concept for the Laboratory Microfusion Facility and to develop a coordinated plan for the realization of an LMC. As originally proposed, the LMC study was divided into two phases. The first phase identifies the purpose and potential utility of the LMC, the regime of its performance parameters, driver independent design issues and requirements, its development goals and requirements, and associated technical, management, staffing, environmental, and other developmental and operational issues. The second phase addresses driver-dependent issues such as specific design, range of performance capabilities, and cost. The study includes four driver options; the neodymium-glass solid state laser, the krypton fluoride excimer gas laser, the light-ion accelerator, and the heavy-ion induction linear accelerator. The results of the Phase II study are described in the present report.

Not Available

1993-05-01

115

Field studies on dominant rodents and the efficacy of certain insecticides to their fleas in Dakahlia Governorate, Egypt.  

PubMed

A preliminary survey of domestic rodent and the efficacy of bendiocarb, diazinon and pirimiphos-methyl insecticides to their fleas were carried out in Dakahlia Governorates (Aga, Meet-Ghamr, El-Senbellawen, Temi El-Amded, Beni-Abed, Dekernes, Nabarow, Talkha, Menia El-Nasr and El-Kordy). Rodent index (number of rodent/trap) and percentage frequency of drodent species were recorded from October 2010 to May 2011. The main rodent species found were the Norway rat, Rattus norvegicus, the grey-bellied rat, R. rattus alexandrinus, the white-bellied rat, R. r. frugivorus and the house mouse, Mus musculus. The rodent index at Beni-Abed, Nabarow, Meet-Ghamr, Dekernes and El-Kordy centers showed 0.46, 0.39, 0.34, 0.33 & 0.33, respectively, while Menia El-Nasr center showed the lowest (0.08). Aga, Talkha, El-Senbellawen, and Temi El-Amded centers showed moderate (0.25, 0.21, 0.2 & 0.16, respectively). The commonest flea species was the oriental rat flea, Xenopsylla cheopis, the mouse flea, Leptopsylla segnis, the dog flea, Ctenocephalides canis and the sticktight flea Echidnophaga gallinacea. The highest number of fleas was on R. norvegicus (Flea index=10.9) while lowest number was on Mus musculus (Flea index=0.1). X. cheopis was the highest frequency distributed for all domestic rodent species (60.9%), while, C. canis was the lowest (1.6%). The results showed that bendiocarb was effective (Lc50=0.389%) than diazinon (Lc50=1.039%) and pirimiphosmethyl (Lc50=2.056 %). PMID:21980770

Soliman, Mohamed Ismail; Mikhail, Micheal William

2011-08-01

116

Rodent phylogeny revised: analysis of six nuclear genes from all major rodent clades  

PubMed Central

Background Rodentia is the most diverse order of placental mammals, with extant rodent species representing about half of all placental diversity. In spite of many morphological and molecular studies, the family-level relationships among rodents and the location of the rodent root are still debated. Although various datasets have already been analyzed to solve rodent phylogeny at the family level, these are difficult to combine because they involve different taxa and genes. Results We present here the largest protein-coding dataset used to study rodent relationships. It comprises six nuclear genes, 41 rodent species, and eight outgroups. Our phylogenetic reconstructions strongly support the division of Rodentia into three clades: (1) a "squirrel-related clade", (2) a "mouse-related clade", and (3) Ctenohystrica. Almost all evolutionary relationships within these clades are also highly supported. The primary remaining uncertainty is the position of the root. The application of various models and techniques aimed to remove non-phylogenetic signal was unable to solve the basal rodent trifurcation. Conclusion Sequencing and analyzing a large sequence dataset enabled us to resolve most of the evolutionary relationships among Rodentia. Our findings suggest that the uncertainty regarding the position of the rodent root reflects the rapid rodent radiation that occurred in the Paleocene rather than the presence of conflicting phylogenetic and non-phylogenetic signals in the dataset. PMID:19341461

Blanga-Kanfi, Shani; Miranda, Hector; Penn, Osnat; Pupko, Tal; DeBry, Ronald W; Huchon, Dorothée

2009-01-01

117

A Scatterometer System for Laboratory Study of Polarimetric Electromagnetic Signatures  

E-print Network

1 A Scatterometer System for Laboratory Study of Polarimetric Electromagnetic Signatures of Icy, an experimental approach was designed with the assistance of a controlled laboratory environment. An advanced

Zhang, Guifu

118

Lurking in the Shadows: Emerging Rodent Infectious Diseases  

PubMed Central

Rodent parvoviruses, Helicobacter spp., murine norovirus, and several other previously unknown infectious agents have “emerged” in laboratory rodents relatively recently. These agents have been discovered serendipitously or through active investigation of atypical serology results, cell culture contamination, unexpected histopathology, or previously unrecognized clinical disease syndromes. The potential research impact of these agents is not fully known. Infected rodents have demonstrated immunomodulation, tumor suppression, clinical disease (particularly in immunodeficient rodents), and histopathology. Perturbations of organismal and cellular physiology also likely occur. These agents posed unique challenges to laboratory animal resource programs once discovered; it was necessary to develop specific diagnostic assays and an understanding of their epidemiology and transmission routes before attempting eradication, and then evaluate eradication methods for efficacy. Even then management approaches varied significantly, from apathy to total exclusion, and such inconsistency has hindered the sharing and transfer of rodents among institutions, particularly for genetically modified rodent models that may not be readily available. As additional infectious agents are discovered in laboratory rodents in coming years, much of what researchers have learned from experiences with the recently identified pathogens will be applicable. This article provides an overview of the discovery, detection, and research impact of infectious agents recently identified in laboratory rodents. We also discuss emerging syndromes for which there is a suspected infectious etiology, and the unique challenges of managing newly emerging infectious agents. PMID:18506061

Besselsen, David G.; Franklin, Craig L.; Livingston, Robert S.; Riley, Lela K.

2013-01-01

119

Laboratory studies in ultraviolet solar physics  

NASA Technical Reports Server (NTRS)

The research activity comprised the measurement of basic atomic processes and parameters which relate directly to the interpretation of solar ultraviolet observations and to the development of comprehensive models of the component structures of the solar atmosphere. The research was specifically directed towards providing the relevant atomic data needed to perform and to improve solar diagnostic techniques which probe active and quiet portions of the solar chromosphere, the transition zone, the inner corona, and the solar wind acceleration regions of the extended corona. The accuracy with which the physical conditions in these structures can be determined depends directly on the accuracy and completeness of the atomic and molecular data. These laboratory data are used to support the analysis programs of past and current solar observations (e.g., the Orbiting solar Observatories, the Solar Maximum Mission, the Skylab Apollo Telescope Mount, and the Naval Research Laboratory's rocket-borne High Resolution Telescope and Spectrograph). In addition, we attempted to anticipate the needs of future space-borne solar studies such as from the joint ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft. Our laboratory activities stressed two categories of study: (1) the measurement of absolute rate coefficients for dielectronic recombination and electron impact excitation; and (2) the measurement of atomic transition probabilities for solar density diagnostics. A brief summary of the research activity is provided.

Parkinson, W. H.; Kohl, J. L.; Gardner, L. D.; Raymond, J. C.; Smith, P. L.

1991-01-01

120

Laboratory and theoretical studies of baroclinic processes  

NASA Technical Reports Server (NTRS)

An understanding is being developed for processes which may be important in the atmosphere, and the definition and analysis of baroclinic experiments utilizing the geophysical fluid flow cells (GFFC) apparatus in microgravity space flights. Included are studies using numerical codes, theoretical models, and terrestrial laboratory experiments. The numerical modeling is performed in three stages: calculation of steady axisymmetric flow, calculation of fastest-growing linear eigenmodes, and nonlinear effects (first, wave-mean flow interactions, then wave-wave interactions). The code can accommodate cylindrical, spherical, or channel geometry. It uses finite differences in the vertical and meridional directions, and is spectral in the azimuthal. The theoretical work was mostly in the area of effects of topography upon the baroclinic instability problem. The laboratory experiments are performed in a cylindrical annulus which has a temperture gradient imposed upon the lower surface and an approximately isothermal outer wall, with the upper and inner surfaces being nominally thermally insulating.

Miller, Timothy; Leslie, Fred W.; Fitzjarrald, Dan; Reynolds, Nathaniel D.; Chou, Shih-Hung; Payne, Karen; Fehribach, Joseph

1989-01-01

121

Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents  

Microsoft Academic Search

Berberis aristata is an edible plant employed in the South Asian Traditional Medicine, particularly its fruits being used as a tonic remedy for liver and heart. In this investigation, berberine, a known compound from this plant, was studied for its possible antihepatotoxic action in rats. Pretreatment of animals with berberine (4 mg\\/kg; orally twice daily for 2 days) prevented the

K. H Janbaz; A. H Gilani

2000-01-01

122

Allometric disparity in rodent evolution  

PubMed Central

In this study, allometric trajectories for 51 rodent species, comprising equal representatives from each of the major clades (Ctenohystrica, Muroidea, Sciuridae), are compared in a multivariate morphospace (=allometric space) to quantify magnitudes of disparity in cranial growth. Variability in allometric trajectory patterns was compared to measures of adult disparity in each clade, and dietary habit among the examined species, which together encapsulated an ecomorphological breadth. Results indicate that the evolution of allometric trajectories in rodents is characterized by different features in sciurids compared with muroids and Ctenohystrica. Sciuridae was found to have a reduced magnitude of inter-trajectory change and growth patterns with less variation in allometric coefficient values among members. In contrast, a greater magnitude of difference between trajectories and an increased variation in allometric coefficient values was evident for both Ctenohystrica and muroids. Ctenohystrica and muroids achieved considerably higher adult disparities than sciurids, suggesting that conservatism in allometric trajectory modification may constrain morphological diversity in rodents. The results provide support for a role of ecology (dietary habit) in the evolution of allometric trajectories in rodents. PMID:23610638

Wilson, Laura A B

2013-01-01

123

Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans.  

PubMed

Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, ?-linolenic acid. Using complimentary cell, rodent and human studies we investigated the impact of anthocyanins and anthocyanin-rich foods/extracts on plasma and tissue EPA and DHA levels and on the expression of fatty acid desaturase 2 (FADS2), which represents the rate limiting enzymes in EPA and DHA synthesis. In experiment 1, rats were fed a standard diet containing either palm oil or rapeseed oil supplemented with pure anthocyanins for 8 weeks. Retrospective fatty acid analysis was conducted on plasma samples collected from a human randomized controlled trial where participants consumed an elderberry extract for 12 weeks (experiment 2). HepG2 cells were cultured with ?-linolenic acid with or without select anthocyanins and their in vivo metabolites for 24 h and 48 h (experiment 3). The fatty acid composition of the cell membranes, plasma and liver tissues were analyzed by gas chromatography. Anthocyanins and anthocyanin-rich food intake had no significant impact on EPA or DHA status or FADS2 gene expression in any model system. These data indicate little impact of dietary anthocyanins on n-3 PUFA distribution and suggest that the increasingly recognized benefits of anthocyanins are unlikely to be the result of a beneficial impact on tissue fatty acid status. PMID:25573539

Vauzour, David; Tejera, Noemi; O'Neill, Colette; Booz, Valeria; Jude, Baptiste; Wolf, Insa M A; Rigby, Neil; Silvan, Jose Manuel; Curtis, Peter J; Cassidy, Aedin; de Pascual-Teresa, Sonia; Rimbach, Gerald; Minihane, Anne Marie

2015-03-01

124

Ultrastructural features of masseter muscle exhibiting altered occlusal relationship - a study in a rodent model  

SciTech Connect

The role of occlusion on Tempormandibular Disorders (TMD) is still unclear, mainly regarding muscular function. The aim of this study was to evaluate the occlusion highlights on masseter ultra morphology. Twenty Wistar rats were randomly divided in four groups: 10 for control group, 10 for occlusal alteration group (CCO). Rats underwent unilateral amputation of the left inferior and superior molar cusps to simulate an occlusal wear situation. The rats of control group had no occlusal wear. Half of the animals of each group was sacrificed in 14 days after the occlusal consuming and half 30 days after the occlusal consuming. The masseter muscles ipsilateral to the amputated molars were excised and processed for light microscopy, electron microscopy. The light microscopy did not show differences between the groups. The electron microscopy was able to detect a degree of intracellular damage in muscle fibers of CCO group: swollen mitochondria with disrupted cristae and cleared matrix, signs of hypercontraction of I bands and myofibril disorganization.

Lisboa, Marcio V.; Aciole, Gilberth T. S.; Oliveira, Susana C. P. S.; Marques, Aparecida M. C.; Pinheiro, Antonio L. B.; Santos, Jean N. [School of Dentistry, Federal University of Bahia, Salvador, BA, 40110-150 (Brazil); Baptista, Abrahao F.; Aguiar, Marcio C. [Biomorphology Department, Federal University of Bahia, Bahia, 40110-150 (Brazil)

2010-05-31

125

Ultrastructural features of masseter muscle exhibiting altered occlusal relationship—a study in a rodent model  

NASA Astrophysics Data System (ADS)

The role of occlusion on Tempormandibular Disorders (TMD) is still unclear, mainly regarding muscular function. The aim of this study was to evaluate the occlusion highlights on masseter ultra morphology. Twenty Wistar rats were randomly divided in four groups: 10 for control group, 10 for occlusal alteration group (CCO). Rats underwent unilateral amputation of the left inferior and superior molar cusps to simulate an occlusal wear situation. The rats of control group had no occlusal wear. Half of the animals of each group was sacrificed in 14 days after the occlusal consuming and half 30 days after the occlusal consuming. The masseter muscles ipsilateral to the amputated molars were excised and processed for light microscopy, electron microscopy. The light microscopy did not show differences between the groups. The electron microscopy was able to detect a degree of intracellular damage in muscle fibers of CCO group: swollen mitochondria with disrupted cristae and cleared matrix, signs of hypercontraction of I bands and myofibril disorganization.

Lisboa, Marcio V.; Aciole, Gilberth T. S.; Oliveira, Susana C. P. S.; Marques, Aparecida M. C.; Baptista, Abrahão F.; Pinheiro, Antonio L. B.; Aguiar, Marcio C.; Santos, Jean N.

2010-05-01

126

Evidence for rodent-common and species-typical limb and digit use in eating, derived from a comparative analysis of ten rodent species.  

PubMed

Order Rodentia comprises a vast portion of mammalian species (1814 species), which occupy extremely diverse habitats requiring very distinct motor specializations (e.g. burrowing, hopping, climbing, flying and swimming). Although early classification of paw use ability suggests rodents are impoverished relative to primates and make little use of their paws, there have been no systematic investigations of paw use in rodents. The present study was undertaken to describe limb/paw movements in a variety of common rodents. The movements used for handling sunflower seeds and other foods were videorecorded and analyzed in the guinea pig (Cavia porcellus), Mongolian gerbil (Meriones unguiculatus), Syrian hamster (Mesocricetus auratus), laboratory mouse (Mus musculus), laboratory rat (Rattus norvegicus), gray squirrel (Sciurus carolinensis), red squirrel (Tamiasciurus hudsonicus), Richardson's ground squirrel (Spermophilus richardsonni), prairie dog (Cynomus parvidens), and Canadian beaver (Castor americanus). The results suggested five order-common movements of food handling: (1) locating food by sniffing, (2) grasping food by mouth, (3) sitting back on the haunches to eat, (4) grasping the food using an elbow-in movement, and (5) manipulate the food with the digits. Different species displayed species-typical specializations including (1) bilateral grasping with the paws (gerbil), (2) unilateral grasping with a paw (beaver), (3) unilateral holding (ground squirrels), (4) various grip and digit postures (all species), (5) unilateral object removal from the mouth (gerbil), (6) bilateral thumb holding (squirrels), and (7) simultaneous holding/manipulation of two objects (squirrels). Only the guinea pig did not handle food with its paws, suggesting its behavior is regressive. The existence of a core pattern of paw and digit use in rodents suggests that skilled limb and paw movements originate at least with the common ancestors of the rodent, and likely the common ancestor to rodent and primate lineages, while species-typical movements suggest specialization/regression of limb use has occurred in a number of mammalian orders. PMID:9821545

Whishaw, I Q; Sarna, J R; Pellis, S M

1998-11-01

127

PRELIMINARY GASTROINTESTINAL STUDIES OF METHANOL EXTRACT OF INDIGOFERA PULCHRA WILLD IN RODENTS.  

PubMed

In this study, the effect of the methanol extract of Indigofera pulchra Willd. (Papillionaceae) was investigated against castor oil induced diarrheoa. Its effects on perfused isolated rabbit jejunum and guinea pig ileum were also evaluated. The extract produced a dose-dependent protection against the castor oil-induced diarrheoa in mice with the highest protection (100%), obtained at 200 mgkg-1 comparable to that of loperamide (5 mgkg-1), a standard antidiarrhoeal drug. The extract (0.4 - 6.4 mgml-1) produced a concentration relaxation of the rabbit jejunum. However, no observable effect was noticed when the guinea pig ileum was treated. The extract blocked the contractile effect of acetylcholine (2 × 10-8 gml-1) and histamine (4 × 10-7 gml-1) on both rabbit jejunum and guinea pig ileum. Phytochemical screening revealed the presence of flavonoids, tannins, saponins and steroids. The intraperitoneal median lethal dose (LD50) value for the extract was found to be 2154.0 mgkg-1. The results obtained revealed that the extract possesses pharmacologically active compounds with gastrointestinal relaxant and antidiarrhoeal activities and may possibly explain the use of the plant in traditional medicine for the treatment of gastrointestinal disorder. PMID:21197141

Musa, A M; Sule, M I; Haruna, A K; Ilyas, M; Iliya, I; Yaro, A H; Magaji, M G

2008-03-01

128

ART and health: clinical outcomes and insights on molecular mechanisms from rodent studies  

PubMed Central

Since the birth of the first IVF-conceived child in 1978, the use of assisted reproductive technologies (ART) has grown dramatically, contributing to the successful birth of 5 million individuals worldwide. However, there are several reported associations of ART with pregnancy complications, such as low birthweight (LBW), preterm birth, birth defects, epigenetic disorders, cancer and poor metabolic health. Whether this is attributed to ART procedures or to the subset of the population seeking ART remains a controversy, but the most relevant question today concerns the potential long-term implications of assisted conception. Recent evidence has emerged suggesting that ART-conceived children have distinct metabolic profiles that may predispose to cardiovascular pathologies in adulthood. Because the eldest IVF individuals are still too young to exhibit components of chronic middle-aged syndromes, the use of animal models has become particularly useful in describing the effects of unusual or stressful preimplantation experiences on adult fitness. Elucidating the molecular mechanisms by which embryos integrate environmental signals into development and metabolic gene expression programs will be essential for optimizing ART procedures such as in vitro culture conditions, embryo selection and transfer. In the future, additional animal studies to identify mechanisms underlying unfavorable ART outcomes, as well as more epidemiological reviews to monitor the long-term health of ART children are required, given that ART procedures have become routine medical practice. PMID:23264495

Feuer, S.K.; Camarano, L.; Rinaudo, P.F.

2013-01-01

129

Genotoxicity studies of rodents exposed to coal dust and diesel emission particulates  

SciTech Connect

Genotoxicity studies with mice and/or rats have been conducted to evaluate the potential mutagenic hazard associated with exposures of coal miners to diesel emission particulates (DEP) and/or coal dusts (CD). Rats and mice were exposed to filtered air, DEP, and/or CD for periods ranging from 3 months to 2 years. The particulate samples extracted with dichloromethane and the urine samples concentrated with XAD-2 columns were analyzed for mutagenic activity by the Ames Salmonella/microsome assay system. Peripheral blood lymphocytes from rats exposed for 3 months were analyzed for sister chromatid exchanges (SCE). The femur bone marrow cells from rats exposed for 24 months and mice exposed for 6 months were analyzed for micronuclei in both polychromatic and normochromatic erythrocytes. The results indicate that the solvent extract of DEP was mutagenic, while no mutagenic activity was found for the CD extract. Combination of CD and DEP did not show any synergistic effect. No mutagenic activity was found for urine samples from rats exposed to DEP and/or CD for up to 2 years. No increase in micronuclei was detected in rats exposed for 24 months. The frequencies of SCE in the peripheral lymphocytes of the 3-month-exposed rats were similar for control and DEP plus CD-exposed groups.

Ong, T.; Whong, W.Z.; Xu, J.; Burchell, B.; Green, F.H.; Lewis, T.

1985-08-01

130

[Role of endoparasites of fleas of wild rodents in plague enzootia].  

PubMed

Laboratory studies of fleas for gregarines have established that it is the latter inhabiting the intestine and stomach of the fleas of wild rodents which are of much interest as protozoa, in whose organism, parasitic species of bacteria can survive. Penetration of plague bacteria into the endoplasm ofgregarines and their possible survival in the cysts may create an additional component in the chain of an epizootic process, which ensures its function, without involving the rodents at the nesting biocenotic level following the pattern: flea imagoes - nesting litter infected with gregarine spores, cysts - flea larvae - flea imagoes infected with cysts, with the plague pathogen emerging into a rodent population through the imago of blocked fleas. PMID:23805483

Chumakova, I V; Tokhov, Iu M

2013-01-01

131

Experimental Study of Ventilation Performance in Laboratories with Chemical Spills  

E-print Network

1 Experimental Study of Ventilation Performance in Laboratories with Chemical Spills Mingang Chemical spills occur frequently in laboratories. The current ventilation code for laboratories recommends a ventilation rate of 12 ACH for maintaining a safe laboratory environment. On the other hand, the energy saving

Chen, Qingyan "Yan"

132

Laboratory study of mini-magnetosphere  

NASA Astrophysics Data System (ADS)

Laboratory study of mini-magnetosphere Magnetosphere at ion kinetic scales, or mini-magnetosphere, which is observed above lunar magnetic anomalies or might be discovered around magnetized asteroids in future missions, possesses unusual features as predicted by numerical simulations. However, there are practically no data on the subject from space observations and the data which is available is far too incomplete. In the present work we describe results of laboratory experiment on interaction of plasma flow with magnetic dipole with parameters such that ion inertia length is smaller than a size of observed magnetosphere. A detailed structure of non-coplanar or out-of-plane component of magnetic field has been obtained in meridian plane. Independence of this component on dipole moment reversal, as was reported in previous works (Shaikhislamov et al 2013, 2014), has been verified. In the tail distinct lobes and central current sheet have been observed. It was found that lobe regions adjacent to boundary layer are dominated by non-coplanar component of magnetic field. Tail-ward oriented electric current in plasma associated with that component appears to be equal to ion current in the frontal part of magnetosphere and in the tail current sheet implying that electrons are stationary in those regions while ions flow by. Obtained data strongly support the proposed model of mini-magnetosphere based on two-fluid effects as described by the Hall term and suggest that spacecraft crossing the tail of magnetized asteroid might observe, instead of simple reversion of tail-ward field, a complex 3-D rotation of magnetic field vector. Acknowledgements This work was supported by SB RAS Research Program grant II.8.1.4, Russian Fund for Basic Research grant 12-02-00367, OFN RAS Research Program 15 and Presidium RAS Research Program 22. References Shaikhislamov, I. F., Antonov, V. M., Zakharov, Yu. P., Boyarintsev, E. L., Melekhov, A. V., Posukh, V. G. and Ponomarenko, A. G. Mini-magnetosphere: Laboratory experiment, physical model and Hall MHD simulation. Adv. in Space Res. 53 422-36, 2013 Shaikhislamov, I. F., Antonov, V. M., Zakharov, Yu. P., Boyarintsev, E. L., Melekhov, A. V., Posukh, V. G. and Ponomarenko, A. G. Experimental study of mini-magnetosphere. Plasma Phys. Control. Fusion 56, 025004 (9pp), 2014

Shaikhislamov, Ildar; Zakharov, Yuri; Posukh, Vitaly; Melekhov, Aleksandr; Antonov, Vladimir; Boyarintsev, Eduard; Ponomarenko, Arnold

133

All Rodents Are Not the Same: A Modern Synthesis of Cortical Organization  

PubMed Central

Rodents are a major order of mammals that is highly diverse in distribution and lifestyle. Five suborders, 34 families, and 2,277 species within this order occupy a number of different niches and vary along several lifestyle dimensions such as diel pattern (diurnal vs. nocturnal), terrain niche, and diet. For example, the terrain niche of rodents includes arboreal, aerial, terrestrial, semi-aquatic, burrowing, and rock dwelling. Not surprisingly, the behaviors associated with particular lifestyles are also highly variable and thus the neocortex, which generates these behaviors, has undergone corresponding alterations across species. Studies of cortical organization in species that vary along several dimensions such as terrain niche, diel pattern, and rearing conditions demonstrate that the size and number of cortical fields can be highly variable within this order. The internal organization of a cortical field also reflects lifestyle differences between species and exaggerates behaviorally relevant effectors such as vibrissae, teeth, or lips. Finally, at a cellular level, neuronal number and density varies for the same cortical field in different species and is even different for the same species reared in different conditions (laboratory vs. wild-caught). These very large differences across and within rodent species indicate that there is no generic rodent model. Rather, there are rodent models suited for specific questions regarding the development, function, and evolution of the neocortex. PMID:21701141

Krubitzer, Leah; Campi, Katharine L.; Cooke, Dylan F.

2011-01-01

134

Rodent Models of Depression: Neurotrophic and Neuroinflammatory Biomarkers  

PubMed Central

Rodent models are an indispensable tool for studying etiology and progress of depression. Since interrelated systems of neurotrophic factors and cytokines comprise major regulatory mechanisms controlling normal brain plasticity, impairments of these systems form the basis for development of cerebral pathologies, including mental diseases. The present review focuses on the numerous experimental rodent models of depression induced by different stress factors (exteroceptive and interoceptive) during early life (including prenatal period) or adulthood, giving emphasis to the data on the changes of neurotrophic factors and neuroinflammatory indices in the brain. These parameters are closely related to behavioral depression-like symptoms and impairments of neuronal plasticity and are both gender- and genotype-dependent. Stress-related changes in expression of neurotrophins and cytokines in rodent brain are region-specific. Some contradictory data reported by different groups may be a consequence of differences of stress paradigms or their realization in different laboratories. Like all experimental models, stress-induced depression-like conditions are experimental simplification of clinical depression states; however, they are suitable for understanding the involvement of neurotrophic factors and cytokines in the pathogenesis of the disease—a goal unachievable in the clinical reality. These major regulatory systems may be important targets for therapeutic measures as well as for development of drugs for treatment of depression states. PMID:24999483

Stepanichev, Mikhail; Dygalo, Nikolay N.; Grigoryan, Grigory; Shishkina, Galina T.; Gulyaeva, Natalia

2014-01-01

135

The Mathematics Laboratory in Engineering Studies.  

ERIC Educational Resources Information Center

Discusses the need for mathematics laboratories to supplement classroom instruction in mathematics for engineering students. Provides a description of such a laboratory, including a listing of equipment and materials that are recommended. Describes the uses for personal computers and suggests various problems that could be explored in the…

Quesada, Jose Fco. Carballido

1986-01-01

136

Rocket and Laboratory Studies in Astronomy  

NASA Technical Reports Server (NTRS)

This is the final report for NASA Grant NAG5-5122 and covers the period from March 1, 1997 to February 28, 2001. This grant was a continuation of a program in rocket and laboratory studies in ultraviolet astronomy that was supported by NASA grant NAG5-619. As of March 1, 2001, this program is continuing under grant NAG5-5315. During the period of the grant, annual status reports have been submitted detailing the scientific achievements and current objectives of each report period. These will not be repeated here. Among the highlights of the program are four successful rocket launches including participation in the campaign to study comet Hale-Bopp in April 1997. We have continued our emphasis on long-slit spectroscopy of extended sources in the shorter wavelength far-ultraviolet, necessitating the development of evacuated telescope/spectrograph payloads. Finally, we also note the use of our ultraviolet calibration facilities in support of other sounding rocket investigators and for other space missions such as the Far Ultraviolet Spectroscopic Explorer. We include a list of the sounding rocket launches performed under NASA sponsorship during this period, a list of Ph.D. degrees awarded to students who worked in this program, and a summary bibliography of publications between 1997 and 2001.

Feldman, Paul D.

2001-01-01

137

The largest fossil rodent  

PubMed Central

The discovery of an exceptionally well-preserved skull permits the description of the new South American fossil species of the rodent, Josephoartigasia monesi sp. nov. (family: Dinomyidae; Rodentia: Hystricognathi: Caviomorpha). This species with estimated body mass of nearly 1000?kg is the largest yet recorded. The skull sheds new light on the anatomy of the extinct giant rodents of the Dinomyidae, which are known mostly from isolated teeth and incomplete mandible remains. The fossil derives from San José Formation, Uruguay, usually assigned to the Pliocene–Pleistocene (4–2?Myr ago), and the proposed palaeoenvironment where this rodent lived was characterized as an estuarine or deltaic system with forest communities. PMID:18198140

Rinderknecht, Andrés; Blanco, R. Ernesto

2008-01-01

138

Infrared laboratory studies of synthetic planetary atmospheres  

NASA Technical Reports Server (NTRS)

The initial stages of the research were involved with a test of Burch's law of multiplicative transmittance for mixed absorbing gases when their lines are broadened by H2 and He, which are constituents of the atmospheres of the major planets. The broadening of individual lines in the CO fundamental by various gases was investigated. Line strength and half-width for individual CO lines were studied as a function of temperature. Measurements of total band absorptance as a function of absorber thickness and total effective pressure were made at various temperatures for bands of CO and N2O. Attempts were made to develop a phenomenological theory of line broadening that would account for the phenomena observed for the CO fundamental and those reported for more highly polar gases. Laboratory measurements of nitric acid vapor absorptance were compared with balloon measurements in arriving at an estimate of the quantity of nitric acid vapor present in the earth's atmosphere in the region of the ozone layer.

Williams, D.

1972-01-01

139

A Study of Mathematics Needed for Dental Laboratory Technology, Medical Laboratory Technology, and Respiratory Therapy.  

ERIC Educational Resources Information Center

A study was conducted to determine what mathematics skills were needed for Dental Laboratory Technology, Medical Laboratory Technology, and Respiratory Therapy. Data obtained from studies, course outlines, textbooks, and reports were used to construct a 79-item mathematics skill questionnaire. This questionnaire was administered to employers,…

Roberts, Keith J.

140

Rocket and Laboratory Studies in Astronomy  

NASA Technical Reports Server (NTRS)

This report covers the period from March 1, 2001 to August 31, 2004. This grant was the continuation of NASA grant NAG5-5122 and supported the Johns Hopkins sounding rocket program that had its roots in the 1960s. The emphasis of this program has been the development of instrumentation for far-ultraviolet astronomy, the training of graduate students in all aspects of a space mission, and the application of these techniques to timely scientific problems. During this period we completed the fabrication of our new long-slit dual-order spectrograph (LIDOS), and successfully flew it on a Black Brant sounding rocket on December 16, 2003 (36.208 UG). The targets were the bright star gamma-Cassiopeiae and its surrounding reflection nebulae, IC 59 and IC 63. We also continued the analysis of the data from our previous flight to study the reflection nebula IC 405 (36.198 UG), which revealed a far-ultraviolet nebular scatter to stellar flux ratio that, contrary to expectations, rises steeply toward the blue. Verifying this result required extensive post-flight analysis and calibration of the Faint Object Telescope FOT) payload, which entailed measuring the telescope mirror reflectivities, the absolute efficiency of the spectrograph, and the telescope point spread function, using a new vacuum collimator developed as part of former graduate student Eric Burgh's Ph.D. dissertation. This work, being done with graduate student Kevin France, has been completed and a paper describing the results has been accepted for publication by the Astrophysical Journal. We have also continued a number of laboratory calibration studies and design efforts.

Feldman, Paul D.; McCandliss, Stephan R.

2004-01-01

141

SPDES Permit Modification Study Brookhaven National Laboratory  

E-print Network

for reduction due to impacts on aquatic organisms. (Copper, Iron, Lead, Nickel, Mercury and Zinc) · Target Water and evaluation in order to determine contributing sources of copper, iron, lead, nickel, zinc, and mercury Bldg. 610 Vehicle Cleaning Bldg. 649 Laboratory Activities Bldgs. 463, 480, 490, 510, 555, 735, 815

Homes, Christopher C.

142

Gene Polymorphism Studies in a Teaching Laboratory  

ERIC Educational Resources Information Center

I present a laboratory procedure for illustrating transcription, post-transcriptional modification, gene conservation, and comparative genetics for use in undergraduate biology education. Students are individually assigned genes in a targeted biochemical pathway, for which they design and test polymerase chain reaction (PCR) primers. In this…

Shultz, Jeffry

2009-01-01

143

The Fecal Viral Flora of Wild Rodents  

PubMed Central

The frequent interactions of rodents with humans make them a common source of zoonotic infections. To obtain an initial unbiased measure of the viral diversity in the enteric tract of wild rodents we sequenced partially purified, randomly amplified viral RNA and DNA in the feces of 105 wild rodents (mouse, vole, and rat) collected in California and Virginia. We identified in decreasing frequency sequences related to the mammalian viruses families Circoviridae, Picobirnaviridae, Picornaviridae, Astroviridae, Parvoviridae, Papillomaviridae, Adenoviridae, and Coronaviridae. Seventeen small circular DNA genomes containing one or two replicase genes distantly related to the Circoviridae representing several potentially new viral families were characterized. In the Picornaviridae family two new candidate genera as well as a close genetic relative of the human pathogen Aichi virus were characterized. Fragments of the first mouse sapelovirus and picobirnaviruses were identified and the first murine astrovirus genome was characterized. A mouse papillomavirus genome and fragments of a novel adenovirus and adenovirus-associated virus were also sequenced. The next largest fraction of the rodent fecal virome was related to insect viruses of the Densoviridae, Iridoviridae, Polydnaviridae, Dicistroviriade, Bromoviridae, and Virgaviridae families followed by plant virus-related sequences in the Nanoviridae, Geminiviridae, Phycodnaviridae, Secoviridae, Partitiviridae, Tymoviridae, Alphaflexiviridae, and Tombusviridae families reflecting the largely insect and plant rodent diet. Phylogenetic analyses of full and partial viral genomes therefore revealed many previously unreported viral species, genera, and families. The close genetic similarities noted between some rodent and human viruses might reflect past zoonoses. This study increases our understanding of the viral diversity in wild rodents and highlights the large number of still uncharacterized viruses in mammals. PMID:21909269

Phan, Tung G.; Kapusinszky, Beatrix; Wang, Chunlin; Rose, Robert K.; Lipton, Howard L.; Delwart, Eric L.

2011-01-01

144

The fecal viral flora of wild rodents.  

PubMed

The frequent interactions of rodents with humans make them a common source of zoonotic infections. To obtain an initial unbiased measure of the viral diversity in the enteric tract of wild rodents we sequenced partially purified, randomly amplified viral RNA and DNA in the feces of 105 wild rodents (mouse, vole, and rat) collected in California and Virginia. We identified in decreasing frequency sequences related to the mammalian viruses families Circoviridae, Picobirnaviridae, Picornaviridae, Astroviridae, Parvoviridae, Papillomaviridae, Adenoviridae, and Coronaviridae. Seventeen small circular DNA genomes containing one or two replicase genes distantly related to the Circoviridae representing several potentially new viral families were characterized. In the Picornaviridae family two new candidate genera as well as a close genetic relative of the human pathogen Aichi virus were characterized. Fragments of the first mouse sapelovirus and picobirnaviruses were identified and the first murine astrovirus genome was characterized. A mouse papillomavirus genome and fragments of a novel adenovirus and adenovirus-associated virus were also sequenced. The next largest fraction of the rodent fecal virome was related to insect viruses of the Densoviridae, Iridoviridae, Polydnaviridae, Dicistroviriade, Bromoviridae, and Virgaviridae families followed by plant virus-related sequences in the Nanoviridae, Geminiviridae, Phycodnaviridae, Secoviridae, Partitiviridae, Tymoviridae, Alphaflexiviridae, and Tombusviridae families reflecting the largely insect and plant rodent diet. Phylogenetic analyses of full and partial viral genomes therefore revealed many previously unreported viral species, genera, and families. The close genetic similarities noted between some rodent and human viruses might reflect past zoonoses. This study increases our understanding of the viral diversity in wild rodents and highlights the large number of still uncharacterized viruses in mammals. PMID:21909269

Phan, Tung G; Kapusinszky, Beatrix; Wang, Chunlin; Rose, Robert K; Lipton, Howard L; Delwart, Eric L

2011-09-01

145

Interlaboratory study of the primary antibody response to sheep red blood cells in outbred rodents following exposure to cyclophosphamide or dexamethasone.  

PubMed

EPA guidelines provide a choice in evaluating humoral immune system function in rats and mice immunized with sheep red blood cells (sRBC): an antibody-forming cell (AFC) assay or a sRBC-specific serum IgM enzyme-linked immunosorbent assay (ELISA). Four different laboratories used both methods to detect suppression of the antibody response by cyclophosphamide (CP) or dexamethasone (DEX). Attempts were made to minimize interlaboratory variability through the use of common reagents and vendors; each laboratory used the same source for rodents, immunosuppressive agents, and one sheep for sRBCs, and determined optimal sRBC concentration for immunization and peak day of antibody response in female CD rats and CD1 mice. The CP dose at which statistical significance was first observed in each species was quite similar within each lab using either assay. For DEX, the AFC assay detected significant and greater suppression at lower concentrations compared to the ELISA in both rats and mice. All labs detected DEX suppression using an AFC assay, whereas only one lab detected significant suppression in both species using an ELISA. For both compounds the magnitude of suppression was greater using the AFC assay, and resulted in ID(50) values which were lower in the AFC assay when compared to the ELISA. In addition, cross-species comparisons of ID(50) values suggested rats were more sensitive than mice. These initial experiments with two chemicals indicated that the AFC assay is consistently better at identifying suppression of a T-dependent antibody response across laboratories following xenobiotic exposures in outbred rats and mice. Additional compounds will need to be evaluated before concluding that one method is superior or more sensitive to the other in detecting suppression of the antibody response. PMID:18958733

Loveless, Scott E; Ladics, Gregory S; Smith, Charlene; Holsapple, Michael P; Woolhiser, Michael R; White, Kimber L; Musgrove, D L; Smialowicz, Ralph J; Williams, W

2007-07-01

146

ACCURACY OF LABORATORY REPORTING IN EPAS WET INTERLABORATORY VARIABILITY STUDY  

EPA Science Inventory

In 1999 and 2000, EPA conducted an interlaboratory variability study of whole effluent toxicity (WET) test methods. This study provided an excellent opportunity to evaluate the accuracy with which laboratories analyzed and reported WET test data. Twenty-eight laboratories reporte...

147

Vehicle and positive control values from the in vivo rodent comet assay and biomonitoring studies using human lymphocytes: historical database and influence of technical aspects.  

PubMed

There is increased interest in the in vivo comet assay in rodents as a follow-up approach for determining the biological relevance of chemicals that are genotoxic in in vitro assays. This is partly because, unlike other assays, DNA damage can be assessed in this assay in virtually any tissue. Since background levels of DNA damage can vary with the species, tissue, and cell processing method, a robust historical control database covering multiple tissues is essential. We describe extensive vehicle and positive control data for multiple tissues from rats and mice. In addition, we report historical data from control and genotoxin-treated human blood. Technical issues impacting comet results are described, including the method of cell preparation and freezing. Cell preparation by scraping (stomach and other GI tract organs) resulted in higher % tail DNA than mincing (liver, spleen, kidney etc) or direct collection (blood or bone marrow). Treatment with the positive control genotoxicant, ethyl methanesulfonate (EMS) in rats and methyl methanesulfonate in mice, resulted in statistically significant increases in % tail DNA. Background DNA damage was not markedly increased when cell suspensions were stored frozen prior to preparing slides, and the outcome of the assay was unchanged (EMS was always positive). In conclusion, historical data from our laboratory for the in vivo comet assay for multiple tissues from rats and mice, as well as human blood show very good reproducibility. These data and recommendations provided are aimed at contributing to the design and proper interpretation of results from comet assays. PMID:24957907

Pant, Kamala; Springer, S; Bruce, S; Lawlor, T; Hewitt, N; Aardema, M J

2014-10-01

148

Microdialysis in Rodents  

PubMed Central

Microdialysis is an in vivo sampling technique that permits the quantification of various substances (e.g., neurotransmitters, peptides, electrolytes) in blood and tissue. It is also used to infuse substances into the brain and spinal cord. This unit describes methods for the construction and stereotaxic implantation of microdialysis probes into discrete brain regions of the rat and mouse. Procedures for the conduct of conventional and quantitative microdialysis experiments in the awake and anesthetized rodent are also provided. PMID:19340813

Zapata, Agustin; Chefer, Vladimir I.; Shippenberg, Toni S.

2010-01-01

149

Competition between harvester ants and rodents in the cold desert  

Microsoft Academic Search

Local distribution patterns of three rodent species (Perognathus parvus, Peromyscus maniculatus, Reithrodontomys megalotis) were studied in areas of high and low densities of harvester ants (Pogonomyrmex owyheei) in Raft River Valley, Idaho. Numbers of rodents were greatest in areas of high ant-density during May, but partially reduced in August; whereas, the trend was reversed in areas of low ant-density. Seed

D. S. Landeen; C. D. Jorgensen; H. D. Smith

1979-01-01

150

Detection of Newly Recognized Rodent Parvoviruses by PCR  

Microsoft Academic Search

Several autonomous parvovirus isolates distinct from the prototypic rodent parvoviruses have recently been identified. These include variants of a mouse orphan parvovirus (MOPV) and a hamster isolate designated hamster orphan parvovirus (HOPV). In this study, a PCR primer set specific for these newly identified rodent parvoviruses was designed on the basis of DNA sequence comparisons of these isolates with other

DAVID G. BESSELSEN; CYNTHIA L. BESCH-WILLIFORD; DAVID J. PINTEL; CRAIG L. FRANKLIN; REUEL R. HOOK; ANDLELA K. RILEY

1995-01-01

151

Rocket and laboratory studies in astronomy  

NASA Technical Reports Server (NTRS)

This report covers the period from September 1, 1992 to August 31, 1993. During the reporting period we launched the Faint Object Telescope to measure absolute fluxes of two hot dwarf stars in the spectral range below 1200 A. Although all systems worked normally, a higher than anticipated pressure in the detector led to ion-feedback that masked the useable data from the source. We have identified the source of the problem and are preparing for a reflight in the Fall of 1993. Our laboratory program for the evaluation of the ultraviolet performance of charge-coupled-detector (CCD) arrays continued with the aim of including a UV-sensitive CCD in a payload to be flown in 1994, and we have begun the assembly of this payload. Work has continued on the analysis of data from previous rocket experiments and from the UVX experiment which flew on STS-61C in January 1986.

Feldman, P. D.

1993-01-01

152

Liver Dysfunction and Phosphatidylinositol-3-Kinase Signalling in Early Sepsis: Experimental Studies in Rodent Models of Peritonitis  

PubMed Central

Background Hepatic dysfunction and jaundice are traditionally viewed as late features of sepsis and portend poor outcomes. We hypothesized that changes in liver function occur early in the onset of sepsis, yet pass undetected by standard laboratory tests. Methods and Findings In a long-term rat model of faecal peritonitis, biotransformation and hepatobiliary transport were impaired, depending on subsequent disease severity, as early as 6 h after peritoneal contamination. Phosphatidylinositol-3-kinase (PI3K) signalling was simultaneously induced at this time point. At 15 h there was hepatocellular accumulation of bilirubin, bile acids, and xenobiotics, with disturbed bile acid conjugation and drug metabolism. Cholestasis was preceded by disruption of the bile acid and organic anion transport machinery at the canalicular pole. Inhibitors of PI3K partially prevented cytokine-induced loss of villi in cultured HepG2 cells. Notably, mice lacking the PI3K? gene were protected against cholestasis and impaired bile acid conjugation. This was partially confirmed by an increase in plasma bile acids (e.g., chenodeoxycholic acid [CDCA] and taurodeoxycholic acid [TDCA]) observed in 48 patients on the day severe sepsis was diagnosed; unlike bilirubin (area under the receiver-operating curve: 0.59), these bile acids predicted 28-d mortality with high sensitivity and specificity (area under the receiver-operating curve: CDCA: 0.77; TDCA: 0.72; CDCA+TDCA: 0.87). Conclusions Liver dysfunction is an early and commonplace event in the rat model of sepsis studied here; PI3K signalling seems to play a crucial role. All aspects of hepatic biotransformation are affected, with severity relating to subsequent prognosis. Detected changes significantly precede conventional markers and are reflected by early alterations in plasma bile acids. These observations carry important implications for the diagnosis of liver dysfunction and pharmacotherapy in the critically ill. Further clinical work is necessary to extend these concepts into clinical practice. Please see later in the article for the Editors' Summary PMID:23152722

Westermann, Martin; Lambeck, Sandro; Lupp, Amelie; Rudiger, Alain; Dyson, Alex; Carré, Jane E.; Kortgen, Andreas; Krafft, Christoph; Popp, Jürgen; Sponholz, Christoph; Fuhrmann, Valentin; Hilger, Ingrid; Claus, Ralf A.; Riedemann, Niels C.; Wetzker, Reinhard; Singer, Mervyn; Trauner, Michael; Bauer, Michael

2012-01-01

153

A Science Librarian in the Laboratory: A Case Study  

ERIC Educational Resources Information Center

A science librarian in the laboratory can become a "point of access" for database instruction and provide a learning opportunity for students to develop their information literacy skills. A case study describes how a librarian in an organic chemistry laboratory helps the class run smoothly and identifies the science librarian as an ally and a…

Tomaszewski, Robert

2011-01-01

154

Original Article Using amphibians in laboratory studies: precautions against  

E-print Network

Original Article Using amphibians in laboratory studies: precautions against the emerging is by far the most widely used amphibian species in laboratories. In the wild, X. laevis is an asymptomatic Batrachochytrium dendrobatidis (Bd), which has devastating effects on wild amphibian populations around the world

Schmeller, Dirk S.

155

Geomagnetic field detection in rodents  

SciTech Connect

In addition to behavioral evidence for the detection of earth-strength magnetic fields (MF) by rodents, recent investigations have revealed that electrophysiological and biochemical responses to MF occur in the pineal organ and retina of rodents. In addition, ferrimagnetic deposits have been identified in the ethmoidal regions of the rodent skull. These findings point to a new sensory phenomenon, which interfaces with many fields of biology, including neuroscience, psychophysics, behavioral ecology, chronobiology and sensory physiology.

Olcese, J.; Reuss, S.; Semm, P.

1988-01-01

156

21 CFR 58.130 - Conduct of a nonclinical laboratory study.  

Code of Federal Regulations, 2011 CFR

...false Conduct of a nonclinical laboratory study. 58.130 Section 58.130 Food...LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of a Nonclinical Laboratory Study § 58.130 Conduct of a...

2011-04-01

157

21 CFR 58.130 - Conduct of a nonclinical laboratory study.  

Code of Federal Regulations, 2010 CFR

...false Conduct of a nonclinical laboratory study. 58.130 Section 58.130 Food...LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of a Nonclinical Laboratory Study § 58.130 Conduct of a...

2010-04-01

158

Experiments on seed predation by rodents and ants in the Israeli desert  

Microsoft Academic Search

Utilization of non-native seeds by seed-eating rodents and ants was studied experimentally in the field. It was found that patterns of granivory in the Israeli deserts are very similar to those reported for the same groups in the deserts of North America. Rodents are more efficient than ants at finding and harvesting seeds. Only rodents can find and harvest seeds

Zvika Abramsky

1983-01-01

159

LABORATORY STUDIES OF PRIORITY POLLUTANT TREATABILITY  

EPA Science Inventory

This study investigated several methods currently available to reduce the level of pollutants in an industrial plant wastewater stream. Its purpose was to screen these treatment processes. As a result of this screening, further in-depth evaluations should be considered. The study...

160

ENVIRONMENTAL RADIOACTIVITY LABORATORY INTERCOMPARISON STUDIES PROGRAM, 1978-1979  

EPA Science Inventory

The U.S. Environmental Protection Agency's intercomparison studies program for laboratories involved in environmental radiation measurements is described. The types of environmental samples distributed, the analyses required for each sample, the distribution schedule, and the sta...

161

ENVIRONMENTAL RADIOACTIVITY LABORATORY INTERCOMPARISON STUDIES PROGRAM, FY 1977  

EPA Science Inventory

The U.S. Environmental Protection Agency's intercomparison studies program for laboratories involved in environmental radiation measurements is described. The types of environmental samples distributed, the analysis required for each sample, the distribution schedule, and the sta...

162

Experimental sleep deprivation as a tool to test memory deficits in rodents.  

PubMed

Paradigms of sleep deprivation (SD) and memory testing in rodents (laboratory rats and mice) are here reviewed. The vast majority of these studies have been aimed at understanding the contribution of sleep to cognition, and in particular to memory. Relatively little attention, instead, has been devoted to SD as a challenge to induce a transient memory impairment, and therefore as a tool to test cognitive enhancers in drug discovery. Studies that have accurately described methodological aspects of the SD protocol are first reviewed, followed by procedures to investigate SD-induced impairment of learning and memory consolidation in order to propose SD protocols that could be employed as cognitive challenge. Thus, a platform of knowledge is provided for laboratory protocols that could be used to assess the efficacy of drugs designed to improve memory performance in rodents, including rodent models of neurodegenerative diseases that cause cognitive deficits, and Alzheimer's disease in particular. Issues in the interpretation of such preclinical data and their predictive value for clinical translation are also discussed. PMID:24379759

Colavito, Valeria; Fabene, Paolo F; Grassi-Zucconi, Gigliola; Pifferi, Fabien; Lamberty, Yves; Bentivoglio, Marina; Bertini, Giuseppe

2013-01-01

163

Experimental sleep deprivation as a tool to test memory deficits in rodents  

PubMed Central

Paradigms of sleep deprivation (SD) and memory testing in rodents (laboratory rats and mice) are here reviewed. The vast majority of these studies have been aimed at understanding the contribution of sleep to cognition, and in particular to memory. Relatively little attention, instead, has been devoted to SD as a challenge to induce a transient memory impairment, and therefore as a tool to test cognitive enhancers in drug discovery. Studies that have accurately described methodological aspects of the SD protocol are first reviewed, followed by procedures to investigate SD-induced impairment of learning and memory consolidation in order to propose SD protocols that could be employed as cognitive challenge. Thus, a platform of knowledge is provided for laboratory protocols that could be used to assess the efficacy of drugs designed to improve memory performance in rodents, including rodent models of neurodegenerative diseases that cause cognitive deficits, and Alzheimer's disease in particular. Issues in the interpretation of such preclinical data and their predictive value for clinical translation are also discussed. PMID:24379759

Colavito, Valeria; Fabene, Paolo F.; Grassi-Zucconi, Gigliola; Pifferi, Fabien; Lamberty, Yves; Bentivoglio, Marina; Bertini, Giuseppe

2013-01-01

164

Lymphocytic Choriomeningitis Virus from Pet Rodents  

MedlinePLUS

... rodent? Rodents, such as mice, hamsters and guinea pigs, are popular as pets in many households. However, ... and pet mice, hamsters, and, on occasion, guinea pigs. What is LCMV? LCMV is carried by rodents ...

165

Laboratory studies of refractory metal oxide smokes  

NASA Technical Reports Server (NTRS)

Studies of the properties of refractory metal oxide smokes condensed from a gas containing various combinations of SiH4, Fe(CO)5, Al(CH3)3, TiCl4, O2 and N2O in a hydrogen carrier stream at 500 K greater than T greater than 1500 K were performed. Ultraviolet, visible and infrared spectra of pure, amorphous SiO(x), FeO(x), AlO(x) and TiO(x) smokes are discussed, as well as the spectra of various co-condensed amorphous oxides, such as FE(x)SiO(y) or Fe(x)AlO(y). Preliminary studies of the changes induced in the infrared spectra of iron-containing oxide smokes by vacuum thermal annealing suggest that such materials become increasingly opaque in the near infrared with increased processing: hydration may have the opposite effect. More work on the processing of these materials is required to confirm such a trend: this work is currently in progress. Preliminary studies of the ultraviolet spectra of amorphous Si2O3 and MgSiO(x) smokes revealed no interesting features in the region from 200 to 300 nm. Studies of the ultraviolet spectra of both amorphous, hydrated and annealed SiO(x), TiO(x), AlO(x) and FeO(x) smokes are currently in progress. Finally, data on the oxygen isotopic composition of the smokes produced in the experiments are presented, which indicate that the oxygen becomes isotopically fractionated during grain condensation. Oxygen in the grains is as much as 3 percent per amu lighter than the oxygen in the original gas stream. The authors are currently conducting experiments to understand the mechanism by which fractionation occurs.

Nuth, Joseph A.; Nelson, R. N.; Donn, Bertram

1989-01-01

166

Epidemiology of Leptospira Transmitted by Rodents in Southeast Asia  

PubMed Central

Background Leptospirosis is the most common bacterial zoonoses and has been identified as an important emerging global public health problem in Southeast Asia. Rodents are important reservoirs for human leptospirosis, but epidemiological data is lacking. Methodology/Principal Findings We sampled rodents living in different habitats from seven localities distributed across Southeast Asia (Thailand, Lao PDR and Cambodia), between 2009 to 2010. Human isolates were also obtained from localities close to where rodents were sampled. The prevalence of Leptospira infection was assessed by real-time PCR using DNA extracted from rodent kidneys, targeting the lipL32 gene. Sequencing rrs and secY genes, and Multi Locus Variable-number Tandem Repeat (VNTR) analyses were performed on DNA extracted from rat kidneys for Leptospira isolates molecular typing. Four species were detected in rodents, L. borgpetersenii (56% of positive samples), L. interrogans (36%), L. kirschneri (3%) and L. weilli (2%), which were identical to human isolates. Mean prevalence in rodents was approximately 7%, and largely varied across localities and habitats, but not between rodent species. The two most abundant Leptospira species displayed different habitat requirements: L. interrogans was linked to humid habitats (rice fields and forests) while L. borgpetersenii was abundant in both humid and dry habitats (non-floodable lands). Conclusion/Significance L. interrogans and L. borgpetersenii species are widely distributed amongst rodent populations, and strain typing confirmed rodents as reservoirs for human leptospirosis. Differences in habitat requirements for L. interrogans and L. borgpetersenii supported differential transmission modes. In Southeast Asia, human infection risk is not only restricted to activities taking place in wetlands and rice fields as is commonly accepted, but should also include tasks such as forestry work, as well as the hunting and preparation of rodents for consumption, which deserve more attention in future epidemiological studies. PMID:24901706

Mielcarek, Mathilde; Tatard, Caroline; Chaval, Yannick; Suputtamongkol, Yupin; Buchy, Philippe; Jittapalapong, Sathaporn; Herbreteau, Vincent; Morand, Serge

2014-01-01

167

Structural insights into the rodent CNS via diffusion tensor imaging  

PubMed Central

Diffusion tensor imaging (DTI) is a useful tool for studying anatomy and pathology in the rodent central nervous system (CNS).The unique tissue contrasts provided by DTI are well suited for monitoring disease progression, studying brain development, and characterizing anatomical phenotypes. Recent technical developments have vastly improved the speed and resolution of rodent DTI. Ongoing research efforts exploring the microstructural basis of DTI signals have provided useful insights into its capabilities to delineate brain structures and detect neuropathology. Significant progress has also been made in combining DTI results with data acquired using other imaging modalities to enhance our understanding of the rodent CNS. PMID:22651954

Zhang, Jiangyang; Aggarwal, Manisha; Mori, Susumu

2012-01-01

168

Analytical evaluation of laboratories wishing to perform environmental characterization studies  

SciTech Connect

Laboratories competing to analyze bivalve mollusks under contract to the National Oceanic and Atmospheric Administration`s Mussel Watch Project were required to undergo analytical tests of their ability to quantify environmental contaminants as part of the contract evaluation process. During the 1989 selection process laboratories that appeared to qualify on the basis of their written proposals were provided a gravimetrically prepared solution with unknown quantities of an undefined number of organic contaminants that are regularly quantified for the Mussel Watch Project. In 1994, competing laboratories were once again tested but this time using matrix materials for the quantification of both trace elements and organic contaminants. Three laboratory groups participated in the exercises. For the 1989 gravimetrically prepared solutions, all participating laboratories were able to identify the contaminants present and in all but two cases were able to report values to within {+-}25% of the known values. In 1994, all laboratories were within the acceptance criteria for the quantification of trace elements in the homogenate sample. Analytical laboratory testing is an important first step to ensure that environmental characterization studies are successful.

Lauenstein, G.G.; Cantillo, A.Y. [National Oceanic and Atmospheric Administration, Silver Spring, MD (United States). National Status and Trends Program

1997-07-01

169

On-site laboratory support of the Oak Ridge National Laboratory remedial investigation\\/feasibility study  

Microsoft Academic Search

In 1987, a remedial investigation\\/feasibility study (RI\\/FS) was begun at Oak Ridge National Laboratory (ORNL). ORNL had established a number of waste area groupings (WAGs), each of which was to be studied and characterized separately. Although the nature and extent of contamination at the WAGs vary widely, samples from each WAG might be radiologically and\\/or chemically contaminated. To comply with

J. L. E. Burn; R. D. Brooksbank; J. L. Dillener; T. R. Jeskie

1992-01-01

170

Cellular plasticity in the supraoptic and paraventricular nuclei after prolonged dehydration in the desert rodent Meriones shawi: Vasopressin and GFAP immunohistochemical study.  

PubMed

Supraoptic (SON) and paraventricular (PVN) nuclei are part of the hypothalamic-neurohypophysial system, they constitute the main source for vasopressin and they represent also obvious examples of activity-dependent neuroglial plasticity. Certain physiological conditions such as dehydration are accompanied by a structural remodeling of the neurons, their synaptic inputs and their surrounding glia. In the present work, an adult Meriones shawi (a rodent adapted to desert life) is used as an animal model. Using GFAP and vasopressin expressions as indicators successively of astrocytes and neuronal activations, the effect of a prolonged episode of water deprivation on the SON and PVN, hypothalamus nuclei were examined. We studied the immunoreactivity of GFAP and vasopressin in various hydration states (total deprivation of drinking water for 1 and 2months compared to hydrated animals). Prolonged dehydration produces an important decrease of GFAP immunoreactivity in both SON and PVN after 1 and 2months of water restriction. This decrease is accompanied by increased vasopressin immunoreactivity following the same periods of water deprivation. These findings may explain a real communication between vasopressin neurons and their surrounding astrocytes, thus the retraction of astrocytes and their processes is accompanied by an enhancement of vasopressin neuron density and their projecting fibers in response to this osmotic stress situation. Furthermore, these data could open further investigations concerning the possible involvement of the communication between astrocytes and vasopressin neurons in both PVN and SON in the regulation of Meriones hydrous balance and resistance to dehydration. PMID:20971098

Gamrani, Halima; Elgot, Abdeljalil; El Hiba, Omar; Fèvre-Montange, Michelle

2011-02-23

171

Laboratory acoustic emission study for earthquake generation process  

NASA Astrophysics Data System (ADS)

Since the similarity in size distribution of earthquakes and acoustic emissions (AE) was found in the 1960s, many laboratory studies have been motivated by the need to provide tools for the prediction of mining failures and natural earthquakes. This paper aims, on the one hand, to draw an outline of laboratory AE studies in the last 50 years, which have addressed seismological problems. Topics include the power laws in which the similarity between AEs and earthquakes is involved and progress that has been made in AE technology and laboratory AE study. On the other hand, this study will highlight some key issues intensively discussed, especially in the last three decades, such as aspects related to the pre-failure damage evolution, fault nucleation and growth in brittle rocks and discuss factors governing these processes.

Lei, Xinglin; Ma, Shengli

2014-12-01

172

A mechanism for resource allocation among sympatric heteromyid rodent species  

Microsoft Academic Search

Laboratory feeding experiments were conducted with Dipodomys ordii and Perognathus flavus in an attempt to discover a mechanism which might result in seed size selection. There was no marked difference in the proportions of four seed types collected whether the rodents foraged in the presence or absence of one another. However, analysis of the variability in weight of each of

Richard L. Hutto

1978-01-01

173

EFFECTIVE VOLE CONTROL WITH ZP RODENT BAIT AG  

Microsoft Academic Search

Since the loss of DDT, Vacor (DPL 787) and other acute rodenticides and the serious use restrictions placed upon strychnine and 1080 for field use, it has become quite apparent that control of field rodents, more particular pine and meadow voles, with standard anticoagulants has become a difficult task, and in some instances impossible. Bell Laboratories, Inc. has chosen to

Edward F. Marshall

1980-01-01

174

A Laboratory Analogue for the Study of Peer Sexual Harassment  

ERIC Educational Resources Information Center

The purpose of this study was to develop a laboratory analogue for the study of peer sexual harassment, and to examine person and situational factors associated with male on female peer sexual harassment. One hundred twenty-two male participants were given the opportunity to tell jokes to a female confederate from a joke list that included…

Mitchell, Damon; Hirschman, Richard; Angelone, D. J.; Lilly, Roy S.

2004-01-01

175

Team Study Training in the College Biology Laboratory  

ERIC Educational Resources Information Center

Students in college biology laboratory classes were grouped heterogeneously or homogeneously according to preferred cognitive learning style and were instructed using the cooperative learning method Student Teams-Achievement Divisions (STAD). In the first year of a two-year study students were given training in a team study strategy. No…

Maloof, Joan; White, Vanessa K. B.

2005-01-01

176

Incorporation of analgesics into rodent embryo transfer protocols: assessing the effects on reproductive outcomes  

E-print Network

Surgical embryo transfer in rodents is a common procedure in today’s research laboratory, although little is known of the effect analgesics may have on not only the recipient female but also the embryos. Two perioperative analgesics, ketoprofen...

Burckhardt, Heather Ann

2009-05-15

177

21 CFR 58.185 - Reporting of nonclinical laboratory study results.  

Code of Federal Regulations, 2010 CFR

...Reporting of nonclinical laboratory study results. 58.185 Section 58...PRACTICE FOR NONCLINICAL LABORATORY STUDIES Records and Reports § 58.185 Reporting of nonclinical laboratory study results. (a) A final report...

2010-04-01

178

21 CFR 58.185 - Reporting of nonclinical laboratory study results.  

Code of Federal Regulations, 2011 CFR

...Reporting of nonclinical laboratory study results. 58.185 Section 58...PRACTICE FOR NONCLINICAL LABORATORY STUDIES Records and Reports § 58.185 Reporting of nonclinical laboratory study results. (a) A final report...

2011-04-01

179

Review: Population Fluctuations in Rodents  

E-print Network

interested in bats. Brock Fenton, Biology, University of Western On- tario, London, Ontario, Canada Population Fluctuations in Rodents. By Charles J. Krebs. Chicago (Illinois): University of Chicago Press. $55.00. x #2; 306 p.; ill.; index. ISBN: 978...

Armitage, Kenneth

2014-03-01

180

A novel variable delay Go/No-Go task to study attention, motivation and working memory in the head-fixed rodent  

PubMed Central

In order to parse the causal elements underlying complex behaviors and decision-making processes, appropriate behavioral methods must be developed and used in concurrence with molecular, pharmacological, and electrophysiological approaches. Presented is a protocol for a novel Go/No-Go behavioral paradigm to study the brain attention and motivation/reward circuitry in awake, head-restrained rodents. This experimental setup allows: (1) Pharmacological and viral manipulation of various brain regions via targeted guide cannula; (2) Optogenetic cell-type specific activation and silencing with simultaneous electrophysiological recording and; (3) Repeated electrophysiological single and multiple unit recordings during ongoing behavior. The task consists of three components. The subject first makes an observing response by initiating a trial by lever pressing in response to distinctive Go or No-Go tones.  Then, after a variable delay period, the subject is presented with a challenge period cued by white noise during which they must respond with a lever press for the Go condition or withhold from lever pressing for the duration of the cue in the No-Go condition. After correctly responding during the challenge period (Challenge) and a brief delay, a final reward tone of the same frequency as the initiation tone is presented and sucrose reward delivery is available and contingent upon lever pressing. Here, we provide a novel procedure and validating data set that allows researchers to study and manipulate components of behavior such as attention, motivation, impulsivity, and reward-related working memory during an ongoing operant behavioral task while limiting interference from non task-related behaviors. PMID:24715953

Cooper, Donald C

2014-01-01

181

The Effects of Arsenic Exposure on Neurological and Cognitive Dysfunction in Human and Rodent Studies: A Review.  

PubMed

Arsenic toxicity is a worldwide health concern as several millions of people are exposed to this toxicant via drinking water, and exposure affects almost every organ system in the body including the brain. Recent studies have shown that even low concentrations of arsenic impair neurological function, particularly in children. This review will focus on the current epidemiological evidence of arsenic neurotoxicity in children and adults, with emphasis on cognitive dysfunction, including learning and memory deficits and mood disorders. We provide a cohesive synthesis of the animal studies that have focused on neural mechanisms of dysfunction after arsenic exposure including altered epigenetics; hippocampal function; glucocorticoid and hypothalamus-pituitary-adrenal axis (HPA) pathway signaling; glutamatergic, cholinergic and monoaminergic signaling; adult neurogenesis; and increased Alzheimer's-associated pathologies. Finally, we briefly discuss new studies focusing on therapeutic strategies to combat arsenic toxicity including the use of selenium and zinc. PMID:24860722

Tyler, Christina R; Allan, Andrea M

2014-01-01

182

COLAB: A Laboratory Environment for Studying Analyst Sensemaking and Collaboration  

E-print Network

Institute 4676 Admiralty Way, Suite 1001 Marina del Rey, California 90292 {clayton,cohen}@isi.edu Abstract COLAB is a laboratory for studying tools that facil- itate collaboration and sensemaking among groups together a large scale terrorist simulator, a collaborative intelligence analysis environment, and a user

Southern California, University of

183

The Coso Geothermal Area: A Laboratory for Advanced MEQ Studies  

E-print Network

- 1 - The Coso Geothermal Area: A Laboratory for Advanced MEQ Studies for Geothermal Monitoring-Dinger Geothermal Program Office, U. S. Navy, China Lake, CA 93555-6001 Keith.Richards-Dinge@navy.mil Keywords of three-component digital seismometers at the Coso geothermal area, California, supplemented by 14

Foulger, G. R.

184

Developing Medicare Competitive Bidding: A Study of Clinical Laboratories  

PubMed Central

Competitive bidding to derive Medicare fees promises several advantages over administered fee systems. The authors show how incentives for cost savings, quality, and access can be incorporated into bidding schemes, and they report on a study of the clinical laboratory industry conducted in preparation for a bidding demonstration. The laboratory industry is marked by variable concentration across geographic markets and, among firms themselves, by social and economic heterogeneity. The authors conclude that these conditions can be accommodated by available bidding design options and by careful selection of bidding markets. PMID:10180003

Hoerger, Thomas J.; Meadow, Ann

1997-01-01

185

Direct injection of whole blood for liquid chromatography/tandem mass spectrometry analysis to support single-rodent pharmacokinetic studies.  

PubMed

Mass spectrometric developments in the last decade enable (sub)nanomolar detection of drug compounds in biological matrices in a few microliters of blood. However, the sampling and especially the handling of these small blood volumes is not straightforward. We studied the feasibility of a recently developed 'sorbent sampling technique' to handle these small blood volumes and the application to support pharmacokinetic (PK) screening programs. This technique applies 5-10 microL of blood on a fibrous material packed into a cartridge. Blood samples absorbed on these cartridges are eluted directly, on-line onto a solid-phase extraction liquid chromatography/tandem mass spectrometry (SPE-LC/MS/MS) system. It is shown that the sorbent sampling technique can be applied for a range of drug compounds. In spite of issues with recovery and sample clean-up that need further improvement, the sorbent sampling technique provided similar data as compared to conventional analytics. The technique was successfully applied to derive kinetic data from individual mice, thereby decreasing the number of required mice for a PK study from 21 to 3. PMID:18286667

Ingelse, Benno A; Vogel, Gerard; Botterblom, Margriet; Nanninga, Dennis; Ooms, Bert

2008-01-01

186

Safety Studies on Intrahepatic or Intratumoral Injection of Oncolytic Vesicular Stomatitis Virus Expressing Interferon-? in Rodents and Nonhuman Primates  

PubMed Central

Abstract Toxicology studies were performed in rats and rhesus macaques to establish a safe starting dose for intratumoral injection of an oncolytic vesicular stomatitis virus expressing human interferon-? (VSV-hIFN?) in patients with hepatocellular carcinoma (HCC). No adverse events were observed after administration of 7.59?×?109 TCID50 (50% tissue culture infective dose) of VSV-hIFN? into the left lateral hepatic lobe of Harlan Sprague Dawley rats. Plasma alanine aminotransferase and alkaline phosphatase levels increased and platelet counts decreased in the virus-treated animals on days 1 and 2 but returned to pretreatment levels by day 4. VSV-hIFN? was also injected into normal livers or an intrahepatic McA-RH7777 HCC xenograft established in Buffalo rats. Buffalo rats were more sensitive to neurotoxic effects of VSV; the no observable adverse event level (NOAEL) of VSV-hIFN? in Buffalo rats was 107 TCID50. Higher doses were associated with fatal neurotoxicity and infectious virus was recovered from tumor and brain. Compared with VSV-hIFN?, toxicity of VSV-rIFN? (recombinant VSV expressing rat IFN-?) was greatly diminished in Buffalo rats (NOAEL, >1010 TCID50). Two groups of two adult male rhesus macaques received 109 or 1010 TCID50 of VSV-hIFN? injected directly into the left hepatic lobe under computed tomographic guidance. No neurological signs were observed at any time point. No abnormalities (hematology, clinical chemistry, body weights, behavior) were seen and all macaques developed neutralizing anti-VSV antibodies. Plasma interleukin-6, tumor necrosis factor-?, and hIFN-? remained below detection levels by ELISA. On the basis of these studies, we will be proposing a cautious approach to dose escalation in a phase I clinical trial among patients with HCC. PMID:19911974

Jenks, Nathan; Myers, Rae; Greiner, Suzanne M.; Thompson, Jill; Mader, Emily K.; Greenslade, Andrew; Griesmann, Guy E.; Federspiel, Mark J.; Rakela, Jorge; Borad, Mitesh J.; Vile, Richard G.; Barber, Glen N.; Meier, Thomas R.; Blanco, Michael C.; Carlson, Stephanie K.; Russell, Stephen J.

2010-01-01

187

Acetate as an active metabolite of ethanol: studies of locomotion, loss of righting reflex, and anxiety in rodents  

PubMed Central

It has been postulated that a number of the central effects of ethanol are mediated via ethanol metabolites: acetaldehyde and acetate. Ethanol is known to produce a large variety of behavioral actions such anxiolysis, narcosis, and modulation of locomotion. Acetaldehyde contributes to some of those effects although the contribution of acetate is less known. In the present studies, rats and mice were used to assess the acute and chronic effects of acetate after central or peripheral administration. Male Sprague-Dawley rats were used for the comparison between central (intraventricular, ICV) and peripheral (intraperitoneal, IP) administration of acute doses of acetate on locomotion. CD1 male mice were used to study acute IP effects of acetate on locomotion, and also the effects of chronic oral consumption of acetate (0, 500, or 1000 mg/l, during 7, 15, 30, or 60 days) on ethanol- (1.0, 2.0, 4.0, or 4.5 g/kg, IP) induced locomotion, anxiolysis, and loss of righting reflex (LORR). In rats, ICV acetate (0.7–2.8 ?moles) reduced spontaneous locomotion at doses that, in the case of ethanol and acetaldehyde, had previously been shown to stimulate locomotion. Peripheral acute administration of acetate also suppressed locomotion in rats (25–100 mg/kg), but not in mice. In addition, although chronic administration of acetate during 15 days did not have an effect on spontaneous locomotion in an open field, it blocked ethanol-induced locomotion. However, ethanol-induced anxiolysis was not affected by chronic administration of acetate. Chronic consumption of acetate (up to 60 days) did not have an effect on latency to, or duration of LORR induced by ethanol, but significantly increased the number of mice that did not achieve LORR. The present work provides new evidence supporting the hypothesis that acetate should be considered a centrally-active metabolite of ethanol that contributes to some behavioral effects of this alcohol, such as motor suppression. PMID:23847487

Pardo, Marta; Betz, Adrienne J.; San Miguel, Noemí; López-Cruz, Laura; Salamone, John D.; Correa, Mercè

2013-01-01

188

METABOLIC AND THERMOREGULATORY RESPONSES OF THE RAT MAINTAINED IN ACRYLIC OR WIRE-SCREEN CAGES: IMPLICATIONS FOR PHARMACOLOGICAL STUDIES  

EPA Science Inventory

Laboratory rodents are usually housed and studied in cages with walls and floor made of ventilated metal or solid plastic materials. It should be recognized that a rodent's thermoregulatory requirements will vary in metal and plastic cages; and it is likely that its metabolic res...

189

Rodent models of TDP-43: Recent advances  

PubMed Central

Recently, missense mutations in the gene TARDBP encoding TDP-43 have been linked to familial ALS. The discovery of genes encoding these RNA binding proteins, such as TDP-43 and FUS/TLS, raised the notion that altered RNA metabolism is a major factor underlying the pathogenesis of ALS. To begin to unravel how mutations in TDP-43 cause dysfunction and death of motor neurons, investigators have employed both gain- and loss-of-function studies in rodent model systems. Here, we will summarize major findings from the initial sets of TDP-43 transgenic and knockout rodent models, identify their limitations, and point to future directions toward clarification of disease mechanism(s) and testing of therapeutic strategies that ultimately may lead to novel therapy for this devastating disease. PMID:22608070

Tsao, William; Jeong, Yun Ha; Lin, Sophie; Ling, Jonathan; Price, Donald L.; Chiang, Po-Min; Wong, Philip C.

2013-01-01

190

RESISTANCE OF AIRBORNE FUNGAL PROPAGULES TO ULTRAVIOLET IRRADIATION: LABORATORY STUDY  

Microsoft Academic Search

The inuence of ultraviolet (UV) radiation on fungi Aspergillus niger Tiegh. isolate OG168, Paecilomyces puntonii (Vuill.) Nann. isolate OG68, and Penicillium expansum Link isolate PO88 was studied under laboratory conditions. A test system was developed for this study. An aerosol chamber provided a dust-free space of 1.5 m3. The source of ultraviolet rays was an UV lamp (DPT 220, 240ñ320

V. Ulevi; D. Pe

191

How toxic is coal ash? A laboratory toxicity case study.  

PubMed

Under a consent agreement among the Environmental Protection Agency (EPA) and proponents both for and against stricter regulation, EPA is to issue a new coal ash disposal rule by the end of 2014. Laboratory toxicity investigations often yield conservative estimates of toxicity because many standard test species are more sensitive than resident species, thus could provide information useful to the rule-making. However, few laboratory studies of coal ash toxicity are available; most studies reported in the literature are based solely on field investigations. This brief communication describes a broad range of toxicity studies conducted for the Tennessee Valley Authority (TVA) Kingston ash spill, results of which help provide additional perspective on the toxicity of coal ash. Integr Environ Assess Manag 2015;11:5-9. © 2014 SETAC. PMID:25348557

Sherrard, Rick M; Carriker, Neil E; Greeley, Mark S

2015-01-01

192

Changes in the abundance of birds in relation to small rodent density and predation rate in Finnish Lapland  

Microsoft Academic Search

The relationships between breeding bird numbers, small rodent density and predation on birds' nests were studied in Finnish Lapland in 1966–87. The cycle length of small rodents was 4–¸5 years. There was a close association between small rodents and the number of Redstart pairs breeding in accessible sites in mountain birch forest, but not with Pied Flycatcher pairs breeding in

A. Järvinen

1990-01-01

193

Evidence for Novel Hepaciviruses in Rodents  

PubMed Central

Hepatitis C virus (HCV) is among the most relevant causes of liver cirrhosis and hepatocellular carcinoma. Research is complicated by a lack of accessible small animal models. The systematic investigation of viruses of small mammals could guide efforts to establish such models, while providing insight into viral evolutionary biology. We have assembled the so-far largest collection of small-mammal samples from around the world, qualified to be screened for bloodborne viruses, including sera and organs from 4,770 rodents (41 species); and sera from 2,939 bats (51 species). Three highly divergent rodent hepacivirus clades were detected in 27 (1.8%) of 1,465 European bank voles (Myodes glareolus) and 10 (1.9%) of 518 South African four-striped mice (Rhabdomys pumilio). Bats showed anti-HCV immunoblot reactivities but no virus detection, although the genetic relatedness suggested by the serologic results should have enabled RNA detection using the broadly reactive PCR assays developed for this study. 210 horses and 858 cats and dogs were tested, yielding further horse-associated hepaciviruses but none in dogs or cats. The rodent viruses were equidistant to HCV, exceeding by far the diversity of HCV and the canine/equine hepaciviruses taken together. Five full genomes were sequenced, representing all viral lineages. Salient genome features and distance criteria supported classification of all viruses as hepaciviruses. Quantitative RT-PCR, RNA in-situ hybridisation, and histopathology suggested hepatic tropism with liver inflammation resembling hepatitis C. Recombinant serology for two distinct hepacivirus lineages in 97 bank voles identified seroprevalence rates of 8.3 and 12.4%, respectively. Antibodies in bank vole sera neither cross-reacted with HCV, nor the heterologous bank vole hepacivirus. Co-occurrence of RNA and antibodies was found in 3 of 57 PCR-positive bank vole sera (5.3%). Our data enable new hypotheses regarding HCV evolution and encourage efforts to develop rodent surrogate models for HCV. PMID:23818848

Drexler, Jan Felix; Corman, Victor Max; Müller, Marcel Alexander; Lukashev, Alexander N.; Gmyl, Anatoly; Coutard, Bruno; Adam, Alexander; Ritz, Daniel; Leijten, Lonneke M.; van Riel, Debby; Kallies, Rene; Klose, Stefan M.; Gloza-Rausch, Florian; Binger, Tabea; Annan, Augustina; Adu-Sarkodie, Yaw; Oppong, Samuel; Bourgarel, Mathieu; Rupp, Daniel; Hoffmann, Bernd; Schlegel, Mathias; Kümmerer, Beate M.; Krüger, Detlev H.; Schmidt-Chanasit, Jonas; Setién, Alvaro Aguilar; Cottontail, Veronika M.; Hemachudha, Thiravat; Wacharapluesadee, Supaporn; Osterrieder, Klaus; Bartenschlager, Ralf; Matthee, Sonja; Beer, Martin; Kuiken, Thijs; Reusken, Chantal; Leroy, Eric M.; Ulrich, Rainer G.; Drosten, Christian

2013-01-01

194

Sensitization to rodents (mouse/rat) in urban atopic populations without occupational exposure living in Campania district (Southern Italy): a multicenter study  

PubMed Central

Background Up to now very few data on allergic sensitization to rodent allergens in Western Europe and Italy are available, and there are no information at district level. The aim of this report was to investigate clinical significance and characteristics of allergic sensitization to mouse/rat (M/Rt) allergens in atopic subjects living in Campania district (Southern Italy). Methods Allergists from the whole Campania district were required to report the results of skin prick tests of at least 100 consecutive subjects. In 1,477 consecutive outpatients, we selected all subjects with an immediate skin reaction to M/Rt dander. Clinical history including a careful evaluation of the modality of exposure and the results of skin-prick tests (SPTs) were recorded. Results Fifty seven patients were sensitized to M/Rt dander (5.78%). Two patients were mono-sensitized. Fourteen patients reported indoor conditions suggesting presence of rodents allergens at home. All patients exhibited low-moderate degree of SPT positivity to M/Rt. High frequency of concomitant allergic sensitization to dust mites was found. Conclusions Our results suggest that the role of allergic sensitization to rodents is not negligible in atopic subjects without occupational exposure living in Campania district area; these values are higher in comparison to those previously found in Naples area. Highly atopic individuals should be tested by SPTs/evaluation of serum specific IgE to rodents in the case they should begin an occupational exposure to M/Rt or keep these animals as pets. PMID:23591013

2013-01-01

195

Optical properties of particles in planetary atmospheres - Laboratory studies  

NASA Technical Reports Server (NTRS)

The laboratory techniques employed for the determination of optical constants are discussed briefly. The values obtained for the real n and imaginary k parts of the refractive indices of water, ice, and liquid ammonia are presented graphically. Work currently in progress on solid ammonia and on sulphuric acid is discussed. Other approaches to studies of the properties of aerosols in planetary atmospheres are presented briefly.

Williams, D.

1974-01-01

196

Laboratory studies of imbibition flooding using carbonated brine  

E-print Network

drying oven maintained at 175 F temperature for 24 hours. The cores were then removed from the oven and placed in a desiccator to cool. The physical properties like, weight, porosity and permeability were determined for each core. A Mettler PE-160..., fractured reservoirs. The laboratory work to conduct imbibition studies was comprised of two phases. Imbibition tests were conducted at room temperature and atmospheric pressure on various sandstone and limestone cores in the first phase. A visual...

Sharif, Qamar Javaid

1991-01-01

197

Laboratory study of potential induced degradation of silicon photovoltaic modules  

Microsoft Academic Search

The standard system architecture of PV installations exposes solar modules to bias voltages of several hundred volts. Recently it became apparent that high bias voltages can have negative effects on the long-term performance of standard screen-printed crystalline silicon solar cells. This paper focuses on the study of this potential induced degradation effect (PID) under laboratory conditions. A corona-discharge assembly was

M. Schutze; M. Junghanel; M. B. Koentopp; S. Cwikla; S. Friedrich; J. W. Muller; P. Wawer

2011-01-01

198

Chromosome damage in wild rodents inhabiting a site contaminated with Aroclor 1254  

SciTech Connect

An in situ investigation of structural chromosomal damage in wild rodents from a site contaminated with Aroclor 1254 was undertaken to compare effects observed in nature to those documented in previous laboratory studies. Laboratory assays indicate that Aroclor 1254 does not cause structural damage to chromosomes. However, the many variables at work in actual waste-site environments and receptor populations led the authors to question whether exposures under natural conditions could potentially lead to different results using the same assay systems. Individuals of three rodent species, Peromyscus leucopus, Sigmodon hispidus, and Reithrodontomys fulvescens, were collected from the contaminated site and three matched, pristine reference sites. Standard somatic metaphase chromosome preparations from bone marrow were examined for chromosomes lesions. Comparisons were made between conspecifics from the Aroclor-contaminated site and the reference sites. Significant increases in chromosome damage were not observed in animals from the Aroclor-contaminated site, indicating agreement between laboratory assays and an in situ application of this assay system.

Shaw-Allen, P.L.; McBee, K. (Oklahoma State Univ., Stillwater (United States))

1993-04-01

199

Short- and long-term effects of litter size manipulation in a small wild-derived rodent.  

PubMed

Iteroparous organisms maximize their overall fitness by optimizing their reproductive effort over multiple reproductive events. Hence, changes in reproductive effort are expected to have both short- and long-term consequences on parents and their offspring. In laboratory rodents, manipulation of reproductive efforts during lactation has however revealed few short-term reproductive adjustments, suggesting that female laboratory rodents express maximal rather than optimal levels of reproductive investment as observed in semelparous organisms. Using a litter size manipulation (LSM) experiment in a small wild-derived rodent (the common vole; Microtus arvalis), we show that females altered their reproductive efforts in response to LSM, with females having higher metabolic rates and showing alternative body mass dynamics when rearing an enlarged rather than reduced litter. Those differences in female reproductive effort were nonetheless insufficient to fully match their pups' energy demand, pups being lighter at weaning in enlarged litters. Interestingly, female reproductive effort changes had long-term consequences, with females that had previously reared an enlarged litter being lighter at the birth of their subsequent litter and producing lower quality pups. We discuss the significance of using wild-derived animals in studies of reproductive effort optimization. PMID:24671828

Lehto Hürlimann, Mikko; Stier, Antoine; Scholly, Olivier; Criscuolo, François; Bize, Pierre

2014-03-01

200

Native Rodent Species Are Unlikely Sources of Infection for Leishmania (Viannia) braziliensis along the Transoceanic Highway in Madre de Dios, Peru  

PubMed Central

An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V.) braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail) were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%), Hylaeamys perenensis (15.7%), and Proechimys spp. (12%). All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V.) braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V.) braziliensis transmission to human inhabitants in this highly prevalent region. PMID:25062033

Shender, Lisa A.; De Los Santos, Maxy; Montgomery, Joel M.; Conrad, Patricia A.; Ghersi, Bruno M.; Razuri, Hugo; Lescano, Andres G.; Mazet, Jonna A. K.

2014-01-01

201

Prospective Power Calculations for the Four Lab Study of A Multigenerational Reproductive/Developmental Toxicity Rodent Bioassay Using A Complex Mixture of Disinfection By-Products in the Low-Response Region  

PubMed Central

In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA’s Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90%) to detect pup weight decreases, while providing the most power to detect increased prenatal loss. PMID:22073030

Dingus, Cheryl A.; Teuschler, Linda K.; Rice, Glenn E.; Simmons, Jane Ellen; Narotsky, Michael G.

2011-01-01

202

Prospective power calculations for the Four Lab study of a multigenerational reproductive/developmental toxicity rodent bioassay using a complex mixture of disinfection by-products in the low-response region.  

PubMed

In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA's Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90%) to detect pup weight decreases, while providing the most power to detect increased prenatal loss. PMID:22073030

Dingus, Cheryl A; Teuschler, Linda K; Rice, Glenn E; Simmons, Jane Ellen; Narotsky, Michael G

2011-10-01

203

Pathology of Rodent Models of Intestinal Cancer: Progress Report and Recommendations  

PubMed Central

In October 2010, a pathology review of rodent models of intestinal neoplasia was held at The Jackson Laboratory. This review complemented 2 other concurrent events: a workshop on methods of modeling colon cancer in rodents and a conference on current issues in murine and human colon cancer. We summarize the results of the pathology review and the committee’s recommendations for tumor nomenclature. A virtual high-resolution image slide box of these models has been developed. This report discusses significant recent developments in rodent modeling of intestinal neoplasia, including the role of stem cells in cancer and the creation of models of metastatic intestinal cancer. PMID:23415801

Washington, Mary Kay; Powell, Anne E.; Sullivan, Ruth; Sundberg, John; Wright, Nicholas; Coffey, Robert J.; Dove, William F.

2013-01-01

204

A study of divergent TA teaching styles in inquiry-based laboratory education  

Microsoft Academic Search

This dissertation is a study of the divergent behaviors evidenced by different TAs teaching inquiry based physics laboratories with minimal preparation on how to use techniques such as Socratic dialogue, wait time, and time management. The revised physics laboratory curricula, a four semester laboratory sequence, were studied over the course of two years and one of the laboratory manuals was

James H. Little

2006-01-01

205

Muon-Induced Background Study for Underground Laboratories  

E-print Network

We provide a comprehensive study of the cosmic-ray muon flux and induced activity as a function of overburden along with a convenient parameterization of the salient fluxes and differential distributions for a suite of underground laboratories ranging in depth from $\\sim$1 to 8 km.w.e.. Particular attention is given to the muon-induced fast neutron activity for the underground sites and we develop a Depth-Sensitivity-Relation to characterize the effect of such background in experiments searching for WIMP dark matter and neutrinoless double beta decay.

D. -M. Mei; A. Hime

2005-12-05

206

Laboratory studies of oil spill bioremediation; toward understanding field behavior  

SciTech Connect

Oil spill remediation aims to enhance the natural process of microbial hydrocarbon biodegradation. The microbial foundations have been studied throughout this century, but the focus of most of this work has been on the degradation of well defined compounds by well defined microbial species. This paper addresses laboratory studies on crude oil biodegradation by microbial consortia obtained from oiled beaches in Prince William Sound, Alaska following the spill from the Exxon Valdez. It demonstrates that oil degradation is indeed likely to be nitrogen-limited in Prince William Sound, the different molecular classes in crude oil that are subjected to biodegradation, the identification of conserved species in the oil that can be used for assessing biodegradation and bioremediation in the field, the effectiveness of fertilizers in stimulating sub-surface biodegradation, the role of the olephilic fertilizer Inipol EAP22, and the identification of the oil-degrading microorganisms in Prince William Sound. Together, these laboratory studies provided guidance and important insights into the microbial phenomena underlying the successful bioremediation of the oiled shorelines.

Prince, R.C.; Hinton, S.M.; Elmendorf, D.L.; Lute, J.R.; Grossman, M.J.; Robbins, W.K.; Hsu, Chang S.; Richard, B.E.; Haith, C.E.; Senius, J.D.; Minak-Bernero, V.; Chianelli, R.R. [Exxon Research and Engineering Co., Annandale, NJ (United States); Bragg, J.R. [Exxon Production Research Co., Houston, TX (United States); Douglas, G.S. [Battelle Ocean Sciences, Duxbury, MA (United States)

1993-12-31

207

Petrochemical-related DNA damage in wild rodents detected by flow cytometry  

SciTech Connect

The need for quick, reliable, in situ tests of environmental mutagenicity is evidenced by increasing public concern about potential health effects of pollutants. Conventional tests of clastogenicity usually involve treatment of laboratory test systems with pure samples of suspect compounds followed by scoring numerous metaphase cells for chromosome aberrations. There are at least two shortcomings of these test protocols. They are very time consumptive and are generally restricted to controlled laboratory situations which may not realistically indicate the effects of environmental pollution. The use of flow cytometry to study resident rodent species as bioindicators provides a system by which cytogenetic effects of environmental pollutants upon exposed organisms rapidly and accurately can be ascertained. The authors found that two species of wild rodents (Peromyscus leucopus and Sigmodon hispidus) living at a dump site polluted with a complex mixture of oil, grease, polychlorinated biphenols, hexachlorobenzene, zinc, manganese, cadmium, chromium, copper, and lead had significantly higher frequencies of chromosomal aberrations than did animals from two unpolluted control sites. These data suggest that resident small mammals may be useful as in situ monitors of the presence and action of mutagenic pollutants in the environment. This study was conducted to determine if changes in patterns of DNA content indicative of the action of mutagens could be detected by flow cytometric analysis of tissues from these same animals.

McBee, K.; Bickham, J.W.

1988-03-01

208

Perampanel, an antagonist of ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, for the treatment of epilepsy: studies in human epileptic brain and nonepileptic brain and in rodent models.  

PubMed

Perampanel [Fycompa, 2-(2-oxo-1-phenyl-5-pyridin-2-yl-1,2-dihydropyridin-3-yl)benzonitrile hydrate 4:3; Eisai Inc., Woodcliff Lake, NJ] is an AMPA (?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor antagonist used as an adjunctive treatment of partial-onset seizures. We asked whether perampanel has AMPA receptor antagonist activity in both the cerebral cortex and hippocampus associated with antiepileptic efficacy and also in the cerebellum associated with motor side effects in rodent and human brains. We also asked whether epileptic or nonepileptic human cortex is similarly responsive to AMPA receptor antagonism by perampanel. In rodent models, perampanel decreased epileptic-like activity in multiple seizure models. However, doses of perampanel that had anticonvulsant effects were within the same range as those engendering motor side effects. Perampanel inhibited native rat and human AMPA receptors from the hippocampus as well as the cerebellum that were reconstituted into Xenopus oocytes. In addition, with the same technique, we found that perampanel inhibited AMPA receptors from hippocampal tissue that had been removed from a patient who underwent surgical resection for refractory epilepsy. Perampanel inhibited AMPA receptor-mediated ion currents from all the tissues investigated with similar potency (IC50 values ranging from 2.6 to 7.0 ?M). Cortical slices from the left temporal lobe derived from the same patient were studied in a 60-microelectrode array. Large field potentials were evoked on at least 45 channels of the array, and 10 ?M perampanel decreased their amplitude and firing rate. Perampanel also produced a 33% reduction in the branching parameter, demonstrating the effects of perampanel at the network level. These data suggest that perampanel blocks AMPA receptors globally across the brain to account for both its antiepileptic and side-effect profile in rodents and epileptic patients. PMID:25027316

Zwart, R; Sher, E; Ping, X; Jin, X; Sims, J R; Chappell, A S; Gleason, S D; Hahn, P J; Gardinier, K; Gernert, D L; Hobbs, J; Smith, J L; Valli, S N; Witkin, J M

2014-10-01

209

Laboratory-Based Studies of Eating among Children and Adolescents  

PubMed Central

The prevalence of pediatric overweight has increased dramatically over the past three decades, likely due to changes in food intake as well as physical activity. Therefore, information examining eating patterns among children and adolescents is needed to illuminate which aspects of eating behavior require modification to prevent and treat pediatric overweight. Because child self-report and parent-report of children's eating habits are often inconsistent and limited by recall and other biases, laboratory-based studies in which food intake is observed and monitored have increased in number. Such studies offer objective and controlled methods of measuring and describing eating behaviors. However, to our knowledge, no publication exists that consolidates, reviews, and provides critical commentary on the literature to date in pediatric samples. In this paper, we review the literature of studies utilizing laboratory methods to examine eating behavior in samples ranging from birth through adolescence. Our review includes all relevant articles retrieved from the PubMed, Medline and PsychInfo search engines. Specifically, we examine meal-feeding studies conducted during the various developmental stages (infancy, preschool, middle childhood, and adolescence), with a focus on methodology. Included in our review are feeding studies related to dietary regulation, exposure and preference, as well as paradigms examining disordered eating patterns and their relationship to body composition. We have structured this review so that both consistent and inconsistent findings are presented by age group, and innovative methods of assessment are discussed in more detail. Following each section, we summarize findings and draw potential conclusions from the available data. We then discuss clinical implications of the research data and suggest directions for the next generation of studies of feeding behavior in children. PMID:19030122

Tanofsky-Kraff, Marian; Haynos, Ann F.; Kotler, Lisa A.; Yanovski, Susan Z.; Yanovski, Jack A.

2008-01-01

210

Toxoplasmosis seroprevalence in urban rodents: a survey in Niamey, Niger  

PubMed Central

A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents - that we reviewed here - which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel. PMID:23828008

Mercier, Aurélien; Garba, Madougou; Bonnabau, Henri; Kane, Mamadou; Rossi, Jean-Pierre; Dardé, Marie-Laure; Dobigny, Gauthier

2013-01-01

211

Toxoplasmosis seroprevalence in urban rodents: a survey in Niamey, Niger.  

PubMed

A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents--that we reviewed here--which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel. PMID:23828008

Mercier, Aurélien; Garba, Madougou; Bonnabau, Henri; Kane, Mamadou; Rossi, Jean-Pierre; Dardé, Marie-Laure; Dobigny, Gauthier

2013-06-01

212

Multiple Co-infections of Rodents with Hantaviruses, Leptospira, and Babesia in Croatia  

PubMed Central

Abstract Hantaviruses, Leptospira spp., and Babesia spp. are rodent-borne pathogens present worldwide. We studied multiple co-infections of small rodents in Croatia with all three pathogens. Twenty-eight Apodemus flavicollis and 16 Myodes glareolus were tested for the presence of hantavirus RNA by real-time RT-PCR, Leptospira strains by renoculture method and Babesia DNA by PCR. Anti-hantavirus antibodies and anti-Leptospira antibodies were detected by serological methods. Very high infection rates with each pathogen were found in A. flavicollis: 20 of 28 rodents (71%) were infected with Dobrava virus, 13 rodents (46%) were infected with Leptospira, and 5 rodents (18%) were infected with Babesia. Multiple co-infections with all three pathogens were found in 3 of 28 (11%) A. flavicollis animals, suggesting that the same rodent host can be infected with several pathogens at the same time. Dual infections with both hantaviruses and Leptospira were found in 7 of 44 rodents (16%), with hantaviruses and Babesia in 2 rodents (5%), and double infection with both Leptospira and Babesia were found in 1 rodent (2%). Since hantaviruses, Leptospira, and Babesia have similar geographical distributions, it is to be expected that in other parts of the world multiple co-infections, representing a serious threat to public health, can be found. PMID:22217170

Turk, Nenad; Korva, Miša; Margaleti?, Josip; Beck, Relja; Vucelja, Marko; Habuš, Josipa; Svoboda, Petra; Županc, Tatjana Avši?; Henttonen, Heikki; Markoti?, Alemka

2012-01-01

213

Persistence of brodifacoum in cockroach and woodlice: implications for secondary poisoning during rodent eradications.  

PubMed

When planning rodent eradications, that normally involve the use of the anticoagulant poison brodifacoum, it is imperative to minimise impacts on other "non-target" species that dwell alongside the targeted rodents and may indeed be the intended beneficiaries of the eradication. Such impacts can arise either from primary poisoning when the non-target species ingest bait pellets containing toxicant or by secondary poisoning when the non-target species eats prey that has itself eaten brodifacoum. Cockroaches and woodlice, likely to scavenge bait pellets, are widely distributed on tropical and sub-tropical islands where they are eaten by ground-dwelling birds. Combining work on Henderson Island, South Pacific, site of a recent rat eradication project, and UK laboratory experiments, our study first measured brodifacoum concentrations in cockroaches given temporary ad lib access to poison bait pellets, approximately mimicking the aftermath of bait distribution for a rodent eradication. In two separate experiments using different species/exposure times, the mean brodifacoum concentrations among cockroaches immediately after bait exposure was 262±s.e. 131 and 477±168µgkg(-1) wet weight. Values decreased quickly in the following 2 weeks, and then continued to decline at a slower rate over the following 4 weeks in the more prolonged laboratory experiment. A supplementary experiment with woodlice recorded a similar brodifacoum concentration in the animals at the end of the exposure period, 223±66µgkg(-1), and a similar time course for the post-exposure decline. In the context of rails (Rallidae), a group of birds known to be particularly susceptible to primary brodifacoum poisoning, these results suggested that, in terms of acute exposure, individual birds would need to eat a minimum of their own body weight (and more commonly 2-5 times that) of live cockroaches before facing a 50% risk of death. Therefore, we conclude that in eradication scenarios, acute secondary poisoning is of lower concern for these birds than primary poisoning. PMID:24008155

de L Brooke, M; Cuthbert, R J; Harrison, G; Gordon, C; Taggart, M A

2013-11-01

214

d-chiro-Inositol is absorbed but not synthesized in rodents  

PubMed Central

d-chiro-Inositol (DCI) and pinitol (1D-3-O-methyl-chiro-inositol) are distinctive inositols reported to possess insulin-mimetic properties. DCI-containing compounds were abundant in common laboratory animal feed. By GC-MS of 6 M-HCl hydrolysates, Purina Laboratory Rodent Diet 5001 (diet 5001) contained 0.23% total DCI by weight with most found in the Lucerne and soy meal components. In contrast, only traces of l-chiro-inositol were observed. The DCI moiety was present in a water-soluble non-ionic form of which most was shown to be pinitol. To measure the absorption of dietary inositols, rats were fed diet 5001 in a balance study or given purified pinitol or [2H6]DCI. More than 98% of the total DCI fed to rats as diet 5001, purified pinitol or [2H6]DCI was absorbed from the gastrointestinal tract. Rats chronically on diet 5001 consumed 921 ?mol total DCI/kg body weight pet d but excreted less than 5.3% in the stool and urine, suggesting that the bulk was metabolized. The levels of pinitol or DCI in plasma, stool, or urine remained relatively stable in mice fed Purina PicoLab® Rodent Diet 20 5053 over a 5-week period, whereas these values declined to very low levels in mice fed a pinitol/DCI-deficient chemically-defined diet. To test whether DCI was synthesized or converted from myo-inositol, mice were treated with heavy water or [2H6]myo-inositol. DCI was neither synthesized endogenously from 2H-labelled water nor converted from [2H6]myo-inositol. DCI and pinitol in rodents appear to be derived solely from the diet. PMID:19586572

Lin, Xiaobo; Ma, Lina; Gopalan, Chaya; Ostlund, Richard E.

2013-01-01

215

Laboratory studies of radionuclide transport in fractured Climax granite  

SciTech Connect

This report documents our laboratory studies of radionuclide transport in fractured granite cores. To simulate natural conditions, our laboratory studies used naturally fractured cores and natural ground water from the Climax Granite Stock at the Nevada Test Site. For comparison, additional tests used artificially fractured granite cores or distilled water. Relative to the flow of tritiated water, {sup 85}Sr and /sup 95m/Tc showed little or no retardation, whereas {sup 137}Cs was retarded. After the transport runs the cores retained varying amounts of the injected radionuclides along the fracture. Autoradiography revealed some correlation between sorption and the fracture fill material. Strontium and cesium retention increased when the change was made from natural ground water to distilled water. Artificial fractures retained less {sup 137}Cs than most natural fractures. Estimated fracture apertures from 18 to 60 {mu}m and hydraulic conductivities from 1.7 to 26 x 10{sup -3} m/s were calculated from the core measurements.

Failor, R.; Isherwood, D.; Raber, E.; Vandergraaf, T.

1982-06-01

216

Laboratory study of biological retention for urban stormwater management.  

PubMed

Urban stormwater runoff contains a broad range of pollutants that are transported to natural water systems. A practice known as biological retention (bioretention) has been suggested to manage stormwater runoff from small, developed areas. Bioretention facilities consist of porous soil, a topping layer of hardwood mulch, and a variety of different plant species. A detailed study of the characteristics and performance of bioretention systems for the removal of several heavy metals (copper, lead, and zinc) and nutrients (phosphorus, total Kjeldahl nitrogen [TKN], ammonium, and nitrate) from a synthetic urban stormwater runoff was completed using batch and column adsorption studies along with pilot-scale laboratory systems. The roles of the soil, mulch, and plants in the removal of heavy metals and nutrients were evaluated to estimate the treatment capacity of laboratory bioretention systems. Reductions in concentrations of all metals were excellent (> 90%) with specific metal removals of 15 to 145 mg/m2 per event. Moderate reductions of TKN, ammonium, and phosphorus levels were found (60 to 80%). Little nitrate was removed, and nitrate production was noted in several cases. The importance of the mulch layer in metal removal was identified. Overall results support the use of bioretention as a stormwater best management practice and indicate the need for further research and development. PMID:11558302

Davis, A P; Shokouhian, M; Sharma, H; Minami, C

2001-01-01

217

Laboratories for the 21st Century: Case Studies; National Renewable Energy Laboratory, Science and Technology Facility, Golden, Colorado  

SciTech Connect

This publication is one in series of case studies for "Laboratories for the 21st Century," a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy Federal Energy Management Program. It is intended for those who plan to design and construct public and private-sector laboratory buildings. This case study describes the Science and Technology Facility, a new laboratory at NREL that incorporated energy-efficient and sustainable design features including underfloor air distribution in offices, daylighting, and process cooling.

Not Available

2007-03-01

218

Selenium neurotoxicity in humans: bridging laboratory and epidemiologic studies.  

PubMed

Selenium is a metalloid of considerable interest in the human from both a toxicological and a nutritional perspective, with a very narrow safe range of intake. Acute selenium intoxication is followed by adverse effects on the nervous system with special clinical relevance, while the neurotoxicity of long-term overexposure is less characterized and recognized. We aimed to address this issue from a public health perspective, focusing on both laboratory studies and the few epidemiologic human studies available, with emphasis on their methodological strengths and limitations. The frequently overlooked differences in toxicity and biological activity of selenium compounds are also outlined. In addition to lethargy, dizziness, motor weakness and paresthesias, an excess risk of amyotrophic lateral sclerosis is the effect on the nervous system which has been more consistently associated with chronic low-level selenium overexposure, particularly to its inorganic compounds. Additional research efforts are needed to better elucidate the neurotoxic effects exerted by selenium overexposure. PMID:24269718

Vinceti, Marco; Mandrioli, Jessica; Borella, Paola; Michalke, Bernhard; Tsatsakis, Aristidis; Finkelstein, Yoram

2014-10-15

219

Preventive effects of Flos Perariae (Gehua) water extract and its active ingredient puerarin in rodent alcoholism models  

E-print Network

YN, Sung CK: Natural medicines for alcoholism treatment: ain rodent alcoholism models. Chinese Medicine 2010 5:36.alcoholism Author details Institute of New Drug Research and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine &

Zhang, Zaijun; Li, Sha; Jiang, Jie; Yu, Pei; Liang, Jing; Wang, Yuqiang

2010-01-01

220

Thieving rodents as substitute dispersers of megafaunal seeds  

PubMed Central

The Neotropics have many plant species that seem to be adapted for seed dispersal by megafauna that went extinct in the late Pleistocene. Given the crucial importance of seed dispersal for plant persistence, it remains a mystery how these plants have survived more than 10,000 y without their mutualist dispersers. Here we present support for the hypothesis that secondary seed dispersal by scatter-hoarding rodents has facilitated the persistence of these large-seeded species. We used miniature radio transmitters to track the dispersal of reputedly megafaunal seeds by Central American agoutis, which scatter-hoard seeds in shallow caches in the soil throughout the forest. We found that seeds were initially cached at mostly short distances and then quickly dug up again. However, rather than eating the recovered seeds, agoutis continued to move and recache the seeds, up to 36 times. Agoutis dispersed an estimated 35% of seeds for >100 m. An estimated 14% of the cached seeds survived to the next year, when a new fruit crop became available to the rodents. Serial video-monitoring of cached seeds revealed that the stepwise dispersal was caused by agoutis repeatedly stealing and recaching each other’s buried seeds. Although previous studies suggest that rodents are poor dispersers, we demonstrate that communities of rodents can in fact provide highly effective long-distance seed dispersal. Our findings suggest that thieving scatter-hoarding rodents could substitute for extinct megafaunal seed dispersers of tropical large-seeded trees. PMID:22802644

Jansen, Patrick A.; Hirsch, Ben T.; Emsens, Willem-Jan; Zamora-Gutierrez, Veronica; Wikelski, Martin; Kays, Roland

2012-01-01

221

Laboratory Studies of Angular Momentum Transport in Astrophysically Relevant Flows  

NASA Astrophysics Data System (ADS)

Rapid angular momentum transport in accretion disks has been a longstanding astrophysical puzzle. Molecular viscosity is inadequate to explain observationally inferred accretion rates. Since Keplerian flow profiles are linearly stable in hydrodynamics, there exist only two viable mechanisms for the required turbulence: nonlinear hydrodynamic instability or magnetorotational instability (MRI). The latter is regarded as a dominant mechanism for rapid angular momentum transport in hot accretion disks ranging from quasars and X-ray binaries to cataclysmic variables. The former has been proposed mainly for cooler protoplanetary disks, whose Reynolds numbers are typically large. Despite their popularity, however, both candidate mechanisms have been rarely demonstrated and studied in the laboratory. In this paper, I will describe a laboratory experiment at Princeton in a short Taylor-Couette flow geometry intended for such purposes. Based on the results from prototype experiments and simulations, the apparatus contains novel features for better controls of the boundary-driven secondary flows. The experiments in water have shown that nonmagnetic quasi-Keplerian flows at Reynolds numbers as large as 2 x10^6 are essentially laminar [1]. Scaled to accretion disks, rates of angular momentum transport lie far below astrophysical requirements. By ruling out hydrodynamic turbulence, our results indirectly support MRI as the likely cause of turbulence even in cool disks. Initial results on MRI, using a liquid gallium eutectic, will be also discussed if available. [1] H. Ji, M. Burin, E. Schartman, & J. Goodman, Nature 444, 343-346 (2006).

Ji, Hantao

2007-04-01

222

Pyrethroids as promising marine antifoulants: laboratory and field studies.  

PubMed

Due to the regulations and bans regarding the use of traditional toxic chemicals against marine fouling organisms and the practical impediments to the commercialization of natural product antifoulants, there is an urgent need for compounds that are antifouling-active, environmentally friendly, and have a potential for commercial application. In this study, a series of common, commercially available pyrethroid products, which are generally used as environmentally safe insecticides, was evaluated for antifouling activity in the laboratory using an anti-settlement test with cyprids of the barnacle Balanus albicostatus and also in a field experiment. Laboratory assay showed that all eleven pyrethroids (namely, rich d-trans-allethrin, Es-biothrin, rich d-prallethrin, S-prallethrin, tetramethrin, rich d-tetramethrin, phenothrin, cyphenothrin, permethrin, cypermethrin, and high active cypermethrin) were able to inhibit barnacle settlement (EC(50) range of 0.0316 to 87.00 microg/ml) without significant toxicity. Analysis of structure-activity relationships suggested that the cyano group at the alpha-carbon position had a significant influence on the expression of antifouling activity in pyrethroids. In the field, the antifouling activity of pyrethroids was further confirmed, with the most potent pyrethroids being cypermethrin and high active cypermethrin, which displayed efficiency comparable with that of tributyltin. In summary, our investigation indicated that these pyrethroids have a great and practical commercial potential as antifouling agents. PMID:18654821

Feng, Danqing; Ke, Caihuan; Li, Shaojing; Lu, Changyi; Guo, Feng

2009-01-01

223

THE USE OF CHEMICALS TO CONTROL FIELD RODENTS AND OTHER PREDATORS. AGRICULTURAL CHEMICALS TECHNOLOGY, NUMBER 5.  

ERIC Educational Resources Information Center

THE PURPOSE OF THIS GUIDE IS TO ASSIST TEACHERS IN PREPARING POST-SECONDARY STUDENTS FOR AGRICULTURAL CHEMICAL OCCUPATIONS. IT IS ONE OF A SERIES OF MODULES DEVELOPED BY A NATIONAL TASK FORCE ON THE BASIS OF DATA FROM STATE STUDIES. SECTIONS ARE (1) USE OF CHEMICALS FOR RODENT CONTROL AND ERADICATION, (2) TERMINOLOGY AND COMPUTATIONS, (3) RODENT

Ohio State Univ., Columbus. Center for Vocational and Technical Education.

224

Laboratory studies of baroclinic instability at small Richardson number  

NASA Technical Reports Server (NTRS)

As part of the support program for the Atmospheric General Circulation Experiment, laboratory studies of baroclinic and other convective instabilities were performed for a thin layer of fluid between thermally conducting horizontal discs. There were three types of modes identified. The first has a spiral-arm appearance, and exists for large enough horizontal thermal forcing, weak enough static stability, and large enough rotation. The source of this wave is shown to be the Eady mode of instability. The second mode is due to convective instability in the thermal boundary layers which exist due to the thermally conducting horizontal boundaries. Finally, for strong enough negative static stability, thermal convection of the Benard type appears. The most significant result is that the symmetric (Solberg) mode was not found, even though the infinite-plane theory predicts this mode under certain experimental conditions.

Miller, T. L.; Fowlis, W. W.

1984-01-01

225

NASA ER-2: Flying Laboratory for Earth Science Studies  

NASA Technical Reports Server (NTRS)

This viewgraph presentation gives an overview of the NASA ER-2 aircraft. The contents include: 1) ER-2 Specifications; 2) ER-2 Basic Configuration; 3) ER-2 Payload Areas: Nose Area; 4) ER-2 Payload Areas: SuperPod Fore and Aftbody; 5) ER-2 Payload Areas: SuperPod Midbody; 6) ER-2 Payload Areas: Q-Bay; 7) ER-2 Payload Areas: Q-Bay Hatch Designs; 8) ER-2 Payload Areas: External Pods; 9) ER-2 Electrical/Control Interface; 10) ER-2 Typical Flight Profile; 11) Tropical Composition, Cloud and Climate Coupling TC-4; 12) TC-4 Timeline; 13) TC4 Area of Interest; 14) ER-2 TC4 Payload; 15) A/C ready for fuel; 16) ER-2 Pilot being suited; 17) ER-2 Taxing; 18) ER-2 Pilot post flight debrief; and 19) NASA ER-2: Flying Laboratory for Earth Science Studies and Remote Sensing.

Navarro, Robert

2007-01-01

226

Laboratory Scale Antifoam Studies for the STTPB Process  

SciTech Connect

Three candidate antifoam/defoam agents were tested on a laboratory scale with simulated KTPB slurry using the proposed STTPB process precipitation, concentration, and washing steps. Conclusions are if air entrainment in the slurry is carefully avoided, little or no foam will be generated during normal operations during precipitation, concentration, and washing of the precipitate. Three candidate antifoam/defoam agents were tested on a laboratory scale with simulated KTPB slurry using the proposed STTPB process precipitation, concentration and washing steps. In all cases little or no foam formed during normal operations of precipitation, concentration and washing. Foam was produced by purposely-introducing gas sub-surface into the slurry. Once produced, the IIT B52 antifoam was effective in defoaming the slurry. In separate foam column tests, all antifoam/defoam agents were effective in mitigating foam formation and in defoaming a foamed 10 wt % insoluble solids slurry. Based on the results in this report as well as foam column studies at IIT, it is recommended that IIT B52 antifoam at the 1000 ppmV level be used in subsequent STTPB work where foaming is a concern. This study indicates that the addition of antifoam agent hinders the recovery of NaTPB during washing. Washing precipitate with no antifoam agent added had the highest level of NaTPB recovery, but had the shortest overall washing time ({approximately}19 hours) compared to 26-28 hours for antifoam runs. The solubilities of the three candidate antifoam/defoam agents were measured in a 4.7 M sodium salt solution. The Surfynol DF-110D defoamer was essentially insoluble while the two IIT antifoamers; Particle Modifier (PM) and B52 were soluble to at least the 2000 ppmV level.

Baich, M.A.

2001-02-13

227

Unexpected primitive rodents in the Quaternary of Argentina  

NASA Astrophysics Data System (ADS)

This article describes the first fossils recorded in the Hernandarias Formation (Pleistocene) in Entre Ríos province (eastern Argentina). They are represented by three teeth assigned to the caviomorph rodents (Rodentia, Mammalia) Aenigmys diamantensis gen. et sp. nov. and Eumysops. To establish the phylogenetic affinities of the two most enigmatic teeth, their enamel microstructure was studied. Aenigmys diamantensis is considered the most primitive taxon of a clade formed by Dinomyidae-Neoepiblemidae-Heptaxodontidae. Evidence of the close relationships among these families also is presented herein. The new fossils reinforce previous hypotheses about the survival of primitive Brazilian taxa after their extinction in the Pampas and Patagonia of southern South America. They also show that the diversity of caviomorph rodents during the Quaternary was greater than supposed and that an important Quaternary extinction, not previously detected, affected several lineages. With the available evidence, it is not possible to determine if these rodents indicate a warm pulse or a particular biogeographic situation in Entre Ríos.

Vucetich, María G.; Vieytes, Emma C.; Verzi, Diego H.; Noriega, Jorge I.; Tonni, Eduardo P.

2005-10-01

228

Teasing Apart the Effects of Seed Size and Energy Content on Rodent Scatter-Hoarding Behavior  

PubMed Central

Scatter-hoarding rodents are known to play a crucial role in the seed dispersal of many plant species. Numerous studies have indicated that both seed size and the energy content of seeds can affect rodent foraging behavior. However, seed size is usually associated with energy content per seed, making it difficult to isolate how seed size and energy affect rodent foraging preferences. This study used 99 treatments of artificial seeds (11 seed sizes×9 levels of energy content) to tease apart the effect of seed size and energy content on rodent seed-caching behavior. Both seed traits showed significant effects, but their details depended on the stage of the rodent foraging process. Seeds with higher energy content were harvested more rapidly while seed size only had a modest effect on harvest rate. However, after harvesting, seed size showed a much stronger effect on rodent foraging behavior. Rodents’ choice of which seeds to remove and cache, as well as seed dispersal distance, seemed to reflect an optimal seed size. Our findings could be adapted in future studies to gain a better understanding of scatter-hoarding rodent foraging behavior, and the co-evolutionary dynamics between plant seed production and seed dispersers. PMID:25350369

Wang, Bo; Yang, Xiaolan

2014-01-01

229

Barnes maze testing strategies with small and large rodent models.  

PubMed

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land (Barnes) mazes. Improved performance over sessions or trials is thought to reflect learning and memory of the escape cage/platform location. Considered less stressful than water mazes, the Barnes maze is a relatively simple design of a circular platform top with several holes equally spaced around the perimeter edge. All but one of the holes are false-bottomed or blind-ending, while one leads to an escape cage. Mildly aversive stimuli (e.g. bright overhead lights) provide motivation to locate the escape cage. Latency to locate the escape cage can be measured during the session; however, additional endpoints typically require video recording. From those video recordings, use of automated tracking software can generate a variety of endpoints that are similar to those produced in water mazes (e.g. distance traveled, velocity/speed, time spent in the correct quadrant, time spent moving/resting, and confirmation of latency). Type of search strategy (i.e. random, serial, or direct) can be categorized as well. Barnes maze construction and testing methodologies can differ for small rodents, such as mice, and large rodents, such as rats. For example, while extra-maze cues are effective for rats, smaller wild rodents may require intra-maze cues with a visual barrier around the maze. Appropriate stimuli must be identified which motivate the rodent to locate the escape cage. Both Barnes and water mazes can be time consuming as 4-7 test trials are typically required to detect improved learning and memory performance (e.g. shorter latencies or path lengths to locate the escape platform or cage) and/or differences between experimental groups. Even so, the Barnes maze is a widely employed behavioral assessment measuring spatial navigational abilities and their potential disruption by genetic, neurobehavioral manipulations, or drug/ toxicant exposure. PMID:24637673

Rosenfeld, Cheryl S; Ferguson, Sherry A

2014-01-01

230

Synanthropic rodents as possible reservoirs of shigatoxigenic Escherichia coli strains  

PubMed Central

Shigatoxigenic Escherichia coli (STEC) strains are worldwide zoonotic pathogen responsible for different cases of human disease including hemolytic uremic syndrome (HUS). Transmission of STEC to humans occurs through the consumption of food and water contaminated by faeces of carriers and by person-to-person contact. The objective of this study was two-fold: (1) to investigate whether synanthropic rodents are possible reservoirs of STEC in the urban area and (2) whether a particular genus out of synanthropic rodent is the principal carrier of STEC. One hundred and forty-five rodents were captured in Buenos Aires City. Screening for stx1/stx2 and rfbO157 was done by PCR from the confluence zone. STEC isolates were further characterized with biochemical tests by standard methods. Additional virulence factors (eae, ehxA, and saa) were also determined by PCR. Forty-one of the rodents were necropsied and sample of kidney and small and large intestine were taken for histopathological diagnosis. The samples sections were stained with hematoxylin-eosin, and observed by light microscopy to evaluate the systemic involvement of these species in natural infections. STEC was isolated from seven out of 27 suspect animals at screening. The following genotypes were found in the STEC strains: stx1/stx2/ehxA (1), stx2 (4), stx2/ehxA (1), stx2/ehxA/eae (1). Neither gross nor microscopic lesions compatible with those produced by Shiga toxin were observed in the studied organs of necropsied rodents. The bivariate analysis including the 145 rodent's data showed that the isolation of STEC is associated positively to Rattus genus. This synanthropic species may play a role in the transmissibility of the agent thus being a risk to the susceptible population. Their control should be included specifically in actions to dismiss the contamination of food and water by STEC in the urban area, as additional strategies for epidemiological control. PMID:23125967

Blanco Crivelli, Ximena; Rumi, María V.; Carfagnini, Julio C.; Degregorio, Osvaldo; Bentancor, Adriana B.

2012-01-01

231

Partnering at the National Laboratories: Catalysis as a Case Study  

SciTech Connect

The role of the national laboratories, particularly the defense program laboratories, since the end of the cold war, has been a topic of continuing debate. The relationship of national laboratories to industry spurred debate which ranged from designating the labs as instrumental to maintaining U.S. economic competitiveness to concern over the perception of corporate welfare to questions regarding the industrial globalization and the possibility of U.S. taxpayer dollars supporting foreign entities. Less debated, but equally important, has been the national laboratories' potential competition with academia for federal research dollars and discussions detailing the role of each in the national research enterprise.

JACKSON,NANCY B.

1999-09-14

232

The AIN-76A defined rodent diet accelerates the development of heart failure in SHHF rats: a cautionary note on its use in cardiac studies.  

PubMed

Previous studies from our laboratory have shown positive benefits of linoleic acid (LA) feeding for attenuation of rat heart failure (HF). However, another research group concluded LA feeding was detrimental to cardiac function, using the American Institute of Nutrition 76A (AIN) diet as a background diet for the experimental animals only. To reconcile these conflicting results and determine whether (i) AIN has effects on cardiovascular function, and (ii) AIN reverses the positive effects of LA feeding, studies were performed using spontaneously hypertensive heart failure (SHHF) rats in both a survival study with lifetime feeding of AIN (control: Purina 5001) and a 2 × 2 factorial design for 6 weeks in young male SHHF rats with background diet and LA as variables. During a lifetime of AIN feeding, mortality from heart failure is significantly accelerated, cardiolipin altered and triglycerides increased. In young rats, 6 weeks on the AIN diet promoted increased systolic and diastolic blood pressure, increased fed and fasting blood glucose, increased serum inflammatory eicosanoids, decreased docosahexanoic acid, increased posterior wall thickness in diastole and an altered cardiolipin subspecies profile. The addition of LA to the AIN diet was able to rescue blood pressure. However, the combination increased retroperitoneal fat mass, body weight and fed blood glucose beyond the levels with the AIN diet alone. Because the AIN diet has wide ranging effects on cardiovascular parameters, our results suggest that it should not be used in animal studies involving the cardiovascular system unless induction of cardiac dysfunction is the desired outcome. PMID:23298172

Rees, M L; Gioscia-Ryan, R A; McCune, S A; Browder, J C; Zachman, D K; Chicco, A J; Johnson, C A; Murphy, R C; Moore, R L; Sparagna, G C

2014-02-01

233

Prevalence and diversity of Bartonella in rodents of northern Thailand: a comparison with Bartonella in rodents from southern China.  

PubMed

We report results of the first study to investigate the distribution and diversity of Bartonella in rodents from Thailand. Whole blood from 195 rodents, representing six species, was tested for the presence of Bartonella species using standard culture techniques. Isolates were obtained from 17 (8.7%) of the samples, and 14 of those isolates represented distinct strains, based upon partial sequencing of the citrate synthase (gltA) gene. Phylogenetic analysis of the isolates and other Bartonella species indicated that five unique isolates from Bandicota indica form a cluster that may represent a new Bartonella species. Two additional isolates from B. indica clustered together, and were nearly identical to an isolate from Apodemus draco collected in southern China. Importantly, a number of the isolates from Thailand rodents are closely related to B. grahamii and B. elizabethae, species which have been associated with human illness. PMID:15100459

Castle, Kevin T; Kosoy, Michael; Lerdthusnee, Kriangkrai; Phelan, Lori; Bai, Ying; Gage, Kenneth L; Leepitakrat, Warisa; Monkanna, Taweesak; Khlaimanee, Nittaya; Chandranoi, Kirkvich; Jones, James W; Coleman, Russell E

2004-04-01

234

ELF electric and magnetic fields: Pacific Northwest Laboratory studies  

SciTech Connect

Studies have been conducted at Battelle, Pacific Northwest Laboratory, to examine extremely-low-frequency (ELF) electromagnetic fields for possible biological effects in animals. Three areas of investigation are reported here: (1) studies on the nervous system, including behavior and neuroendocrine function, (2) experiments on cancer development in animals, and (3) measurements of currents and electric fields induced in animal models by exposure to external magnetic fields. In behavioral experiments, rats have been shown to be responsive to ELF electric field exposure. Furthermore, experimental data indicate that short-term memory may be affected in albino rats exposed to combined ELF and static magnetic fields. Neuroendocrine studies have been conducted to demonstrate an apparent stress-related response in rats exposed to 60-Hz electric fields. Nighttime pineal melatonin levels have been shown to be significantly depressed in animals exposed to either electric or magnetic fields. A number of animal tumor models are currently under investigation to examine possible relationships between ELF exposure and carcinogenesis. Finally, theoretical and experimental measurements have been performed which form the basis for animals and human exposure comparisons.

Anderson, L.E.

1992-06-01

235

Molecular Carbon in the Galaxy: Laboratory and Observational Studies  

NASA Technical Reports Server (NTRS)

In a collaboration with the Mats Larsson group from Stockholm, we carried out a new measurement of the rate of dissociative recombination of H(sup *, sub j), using a new pulsed supersonic beam source of rotationally cold H(sup *, sub j). This source was first designed and characterized in our lab by IR cavity ringdown spectroscopy, determining a rotationaYtranslationa1 temperature of 20-60K, depending on conditions. This new source was then taken to Stockholm for the recombination rate studies at the CRYRING storage ring. The recombination rate constant measured against temperature yields values consistent with the most recent calculations, whereas previous experimental measurements varied over a range of 10(exp 4) and were poor agreement with theory. This is a crucial achievement for understanding the ion chemistry of diffuse clouds. Moreover, this result in combination with recent observations implies a greatly enhanced (factor of 40) cosmic ray ionization rate in a diffuse cloud (zeta Persei) relative to previous studies. The implications of this are discussed in our recent Nature paper. An enhanced cosmic-ray flux towards zeta Persei inferred from a laboratory study of the H(sup *, sub j)-e(sup -) recombination rate.

Saykally, Richard James

2003-01-01

236

Laboratory Study of the Rotational Spectrum of 2-BUTANONE  

NASA Astrophysics Data System (ADS)

Our recent observations of the Orion-KL region in the ? = 1.3 mm window reveal that ˜55% of the observed transitions cannot be assigned to previously identified molecules. In addition, the strongest unidentified transitions have peak intensities on the order of 7 K. This provides strong evidence that new molecules of astrochemical interest need to be studied in the laboratory in order to compare to interstellar spectra. A starting point for this work is to target complex organic molecules that are structurally-similar to molecules that have already been detected in interstellar environments. We have therefore collected the microwave, millimeter, and submillimeter spectra of 2-butanone [also known as methyl ethyl ketone (MEK), CH_3COCH_2CH_3]. MEK is a likely candidate for detection in the ISM because it contains similar functional groups to known and highly abundant interstellar molecules such as ethanol, acetaldehyde, and acetone. The microwave spectrum of MEK was acquired with the chirped-pulse waveguide Fourier Transform Microwave (CP-FTMW) spectrometer at New College of Florida; and the millimeter and submillimeter spectrum was acquired with the direct absorption flow cell spectrometer at Emory University. We have collected the spectrum of MEK from 8 GHz to 1 THz and assigned the ground vibrational state spectrum of MEK from 8 GHz to 500 GHz using the ERHAM program. We will report here on the laboratory characterization and assignment of the MEK spectrum. We will also report on the analysis of observational lines surveys in the context of the identification of new, complex organic molecules such as MEK.

Kroll, Jay A.; Weaver, Susanna L. Widicus; Shipman, Steven T.

2012-06-01

237

Sleep laboratory studies on single dose effects of suriclone.  

PubMed

1. In a double-blind, placebo-controlled sleep laboratory study single doses of suriclone, a new non-benzodiazepine anxiolytic binding to benzodiazepine receptors, were investigated with respect to sleep and awakening. 2. Sixteen healthy young volunteers spent 10 nights in the sleep laboratory: 1 adaptation night, 1 baseline night and 4 drug nights (placebo; 0.2 mg, 0.4 mg suriclone; 2 mg lorazepam as reference drug) and 4 subsequent wash-out nights (drug-interval: 1 week). Somnopolygraphic investigations (22.30 h to 06.00 h) were commenced 0.5 h after drug-intake. A self-rating scale for sleep and awakening quality as well as psychometric tests were completed in the morning. 3. Hypnotic effects were most pronounced after lorazepam in regard to total sleep time and sleep efficiency. After lorazepam as well as after 0.4 mg suriclone nocturnal awakenings decreased significantly as compared with placebo, which was reflected in an improved subjective sleep quality after both dosages. Suriclone 0.2 mg did not induce any alterations in all night sleep. 4. In the morning, well-being, drowsiness and reaction time performance deteriorated after lorazepam as compared with placebo but not after suriclone. The latter was significantly superior to lorazepam with respect to subjective awakening quality, well-being, emotional rapport, drowsiness and attention. 5. Blood pressure and pulse remained unchanged after all of the drugs. Critical flicker frequency and muscle strength decreased only after lorazepam as compared with placebo. PMID:1980201

Saletu, B; Frey, R; Grünberger, J; Krupka, M; Anderer, P; Musch, B

1990-11-01

238

Laboratory Studies of Supersonic Magnetized Plasma Jets and Radiative Shocks  

NASA Astrophysics Data System (ADS)

In this talk I will focus on laboratory plasma experiments producing magnetically driven supersonic plasma jets and on the interaction of these jets with ambient media. The experiments are scalable to astrophysical flows in that the critical dimensionless numbers such as the plasma collisionality, the plasma beta, the Reynolds number and the magnetic Reynolds number are all in the astrophysically appropriate ranges. The experimental results will be compared with computer simulations performed with laboratory plasma codes and with astrophysical codes. In the experiments the jets are driven and collimated by the toroidal magnetic fields and it is found that the level of MHD instabilities in the jets strongly depends on the strength of the field represented by the ratio of the thermal to magnetic field pressures (plasma beta). The experiments show the possibility of formation of episodic outflows, with periodic ejections of magnetic bubbles naturally evolving into a heterogeneous jet propagating inside a channel made of self-collimated magnetic cavities [1,2]. We also found that it is possible to form quasi-laminar jets which are “indirectly” collimated by the toroidal magnetic fields, but this requires the presence of the lower density halo plasma surrounding the central jet [3]. Studies of the radiative shocks formed in the interaction of the supersonic magnetized plasma flows with ambient plasma will be also presented, and the development of cooling instabilities in the post-shock plasma will be discussed. This research was sponsored by EPSRC Grant No. EP/G001324/1 and by the OFES DOE under DOE Cooperative Agreement No. DE-SC-0001063. References 1. A. Ciardi, S.V. Lebedev, A. Frank et al., The Astrophysical Journal, 691: L147-L150 (2009) 2. F.A. Suzuki-Vidal, S.V. Lebedev, S.N. Bland et al., Physics of Plasmas, 17, 112708 (2010). 3. F.A. Suzuki-Vidal, M. Bocchi, S.V. Lebedev et al., Physics of Plasmas, 19, 022708 (2012).

Lebedev, Sergey

2013-06-01

239

Farmer's perceptions of rodents as crop pests : Knowl- edge, attitudes and practices in rodent pest management in Tanzania and Ethiopia  

Microsoft Academic Search

A study was conducted using a structured questionnaire to obtain information about the nature and extent of rodent damage to crops, farmer's perceptions of crop pests and their knowledge, attitudes and practices to their management in Tanzania and Ethiopia. The study was carried out in five localities (Makuyu -Central Tanzania; Chunya-Southwest Tanzania; Ziway and Adami Tulu (south of Addis Ababa)

Rhodes H. Makundi; Afework Bekele; Herwig Leirs; Winnie Rwamugira; Loth S. Mulungu

240

Examining the clinical efficacy of bupropion and nortriptyline as smoking cessation agents in a rodent model of nicotine withdrawal  

Microsoft Academic Search

Rationale  At present, there is a lack of an established animal model to demonstrate the clinical efficacy of smoking cessation agents\\u000a in the laboratory. The aim of this study was to compare the effects of the antidepressants bupropion and nortriptyline, clinically\\u000a proven smoking cessation aids, within a rodent model of a nicotine withdrawal based on somatic measures.\\u000a \\u000a \\u000a \\u000a Materials and methods  Male hooded

V. C. Wing; M. Shoaib

2007-01-01

241

A numerical, laboratory, and field study of riverbed filtration  

NASA Astrophysics Data System (ADS)

Riverbed filtration is an appealing alternative to conventional riverbank and surface water intake systems, offering advantages of high flow rates, natural filtering, and undiminished performance under ice conditions. Its proper functioning requires careful study and monitoring of river flow dynamics, subsurface characteristics, and the interactions between these surface water and groundwater components. A research effort has been underway at INRS to develop principles and guidelines for the design, operation, and maintenance of riverbed filtration systems. A pilot system has just been completed in the Montmorency River near Quebec City (Canada). The installation consists of 4 horizontal wells (or drains), each of 20 m length and 30 cm diameter, placed 4 m apart, at a depth of 1.5 m within the riverbed sediments, and in a direction orthogonal to river flow. The housing trench for each drain is 2 m wide and 2.10 m deep and is composed of 90 cm of gravel topped with 70 cm of sifted alluvial sediments and a 50 cm protective layer of pebbles extracted from the sifted sediments. The average annual water level in the river is 1.2 m, while its mean head during low flow periods is 90 cm. The pilot installation is instrumented with multilevel pressure and temperature sensors and several flowmeters for continuous monitoring in both drainage and backwash modes. In gravity drainage (water intake) mode, the yield is expected to exceed the municipal demand criterion of 35 000 m3/d. Backwash operations, needed to unclog the trenches of fine sediments that can accumulate during water intake, are considered critical to maintaining the design performance targets for the system. Prior to construction of the pilot system, flow patterns, pressure responses, and turbidity behavior in both drainage and backwash modes were extensively studied in laboratory (sand column and sand box) and numerical (SEEP2D) experiments. These tests were fundamental to defining the design parameters and instrumentation features of the pilot system. More detailed lab and numerical simulation studies will be undertaken in tandem with the pilot system operation. The presentation will give an overview of the findings from the prior laboratory and numerical experiments and present initial results from the operation of the pilot system.

Racine, C.; Lefebvre, R.; Martel, R.; Paniconi, C.

2012-04-01

242

Susceptibility of selected rodent species from Colorado to Borrelia burgdorferi.  

PubMed

To determine the susceptibility of some common Colorado (USA) rodent species to Borrelia burgdorferi, pregnant Peromyscus maniculatus, Tamias minimus, and Spermophilus lateralis were trapped in May 1990 and kept in quarantine until their young were old enough to be used in the experiment. Six to eight 8-wk-old individuals of each of the Colorado species and, for comparison, eight laboratory raised P. leucopus were subcutaneously inoculated with > or = 10(5) spirochetes in 0.1 ml in July 1990. Tissue specimens were collected for isolation from these animals through April 1991. Spirochetes were isolated from blood, ear, bladder, kidney, spleen, liver, and eye in Barbour-Stoener-Kelly (BSK) medium from P. maniculatus, P. leucopus and T. minimus. Spirochetes were isolated from at least one tissue from all of these animals and no isolations were obtained from any of the S. lateralis. Thus, three of the four rodent species tested are susceptible to, and could harbor, B. burgdorferi. PMID:8722268

Ubico, S R; McLean, R G; Cooksey, L M

1996-04-01

243

A human laboratory pilot study with baclofen in alcoholic individuals.  

PubMed

Preclinical and clinical studies show that the GABA(B) receptor agonist baclofen may represent a pharmacotherapy for alcohol dependence (AD). However, the mechanisms by which baclofen affects drinking are not well characterized; thus this pilot study investigated possible baclofen's biobehavioral mechanisms. The design was a double-blind controlled randomized human laboratory pilot study. Fourteen non-treatment seeking alcohol-dependent heavy drinking subjects received either baclofen 10mg t.i.d. or an active placebo (cyproheptadine 2mg t.i.d., to control for sedation) for a 7-day period. At day 8, participants performed an alcohol cue-reactivity (CR) followed by an alcohol self-administration (ASA). Additionally, we explored possible moderators that might guide future larger studies, i.e. anxiety, family history and onset of alcoholism, and D4 dopamine receptor (DRD4) and 5-HTTLPR polymorphisms. The main results were a significant effect of baclofen for increasing stimulation (p=.001) and sedation (p<.01). Furthermore, when drinking during the ASA and the 2 days before was analyzed as a composite variable, there was a significant effect of baclofen to reduce alcohol consumption (p<.01). As for the exploratory analyses, baclofen's effects to increase alcohol sedation and to reduce alcohol consumption were limited to those individuals with DRD4 ?7 repeats (DRD4L). Yet, baclofen's effects on alcohol consumption were also moderated by 5-HTTLPR LL genotype. In conclusion, baclofen's ability to reduce alcohol drinking may be related to its effects on the biphasic effects of alcohol, but larger studies are needed to confirm these preliminary findings. PMID:23262301

Leggio, Lorenzo; Zywiak, William H; McGeary, John E; Edwards, Steven; Fricchione, Samuel R; Shoaff, Jessica R; Addolorato, Giovanni; Swift, Robert M; Kenna, George A

2013-02-01

244

A human laboratory pilot study with baclofen in alcoholic individuals  

PubMed Central

Preclinical and clinical studies show that the GABAB receptor agonist baclofen may represent a pharmacotherapy for alcohol dependence (AD). However, the mechanisms by which baclofen affects drinking are not well characterized; thus this pilot study investigated possible baclofen’s biobehavioral mechanisms. The design was a double-blind controlled randomized human laboratory pilot study. Fourteen non-treatment seeking alcohol-dependent heavy drinking subjects received either baclofen 10 mg t.i.d. or an active placebo (cyproheptadine 2 mg t.i.d., to control for sedation) for a 7-day period. At day 8, participants performed an alcohol cue-reactivity (CR) followed by an alcohol self-administration (ASA). Additionally, we explored possible moderators that might guide future larger studies, i.e. anxiety, family history and onset of alcoholism, and D4 dopamine receptor (DRD4) and 5-HTTLPR polymorphisms. The main results were a significant effect of baclofen for increasing stimulation (p=.001) and sedation (p<.01). Furthermore, when drinking during the ASA and the 2 days before was analyzed as a composite variable, there was a significant effect of baclofen to reduce alcohol consumption (p<.01). As for the exploratory analyses, baclofen’s effects to increase alcohol sedation and to reduce alcohol consumption were limited to those individuals with DRD4 ?7 repeats (DRD4L). Yet, baclofen’s effects on alcohol consumption were also moderated by 5-HTTLPR LL genotype. In conclusion, baclofen’s ability to reduce alcohol drinking may be related to its effects on the biphasic effects of alcohol, but larger studies are needed to confirm these preliminary findings. PMID:23262301

Leggio, Lorenzo; Zywiak, William H.; McGeary, John E.; Edwards, Steven; Fricchione, Samuel R.; Shoaff, Jessica R.; Addolorato, Giovanni; Swift, Robert M.; Kenna, George A.

2015-01-01

245

Leaving home: A study of laboratory mouse pup independence  

Microsoft Academic Search

Juvenile wild house mice leave their mothers at 8 weeks (+). In contrast, laboratory strains of mice (lab mice) are typically ‘weaned’ at postnatal day (PND) 21. Lab mice might mature faster than their wild forebears; but if they do not, standard laboratory weaning likely involves maternal deprivation. We therefore investigated when lab mice voluntarily leave their mothers. C57BL\\/6J families

Allison Bechard; Georgia Mason

2010-01-01

246

Neuregulin 1: a prime candidate for research into gene-environment interactions in schizophrenia? Insights from genetic rodent models  

PubMed Central

Schizophrenia is a multi-factorial disease characterized by a high heritability and environmental risk factors. In recent years, an increasing number of researchers worldwide have started investigating the “two-hit hypothesis” of schizophrenia predicting that genetic and environmental risk factors (GxE) interactively cause the development of the disorder. This work is starting to produce valuable new animal models and reveal novel insights into the pathophysiology of schizophrenia. This mini review will focus on recent advancements in the field made by challenging mutant and transgenic rodent models for the schizophrenia candidate gene neuregulin 1 (NRG1) with particular environmental factors. It will outline results obtained from mouse and rat models for various Nrg1 isoforms/isoform types (e.g., transmembrane domain Nrg1, Type II Nrg1), which have been exposed to different forms of stress (acute versus chronic, restraint versus social) and housing conditions (standard laboratory versus minimally enriched housing). These studies suggest Nrg1 as a prime candidate for GxE interactions in schizophrenia rodent models and that the use of rodent models will enable a better understanding of GxE interactions and the underlying mechanisms. PMID:23966917

Karl, Tim

2013-01-01

247

A qualitative case study of instructional support for web-based simulated laboratory exercises in online college chemistry laboratory courses  

NASA Astrophysics Data System (ADS)

This study fills a gap in the research literature regarding the types of instructional support provided by instructors in online introductory chemistry laboratory courses that employ chemistry simulations as laboratory exercises. It also provides information regarding students' perceptions of the effectiveness of that instructional support. A multiple case study methodology was used to carry out the research. Two online introductory chemistry courses were studied at two community colleges. Data for this study was collected using phone interviews with faculty and student participants, surveys completed by students, and direct observation of the instructional designs of instructional support in the online Blackboard web sites and the chemistry simulations used by the participating institutions. The results indicated that the instructors provided multiple types of instructional support that correlated with forms of effective instructional support identified in the research literature, such as timely detailed feedback, detailed instructions for the laboratory experiments, and consistency in the instructional design of lecture and laboratory course materials, including the chemistry lab simulation environment. The students in one of these courses identified the following as the most effective types of instructional support provided: the instructor's feedback, opportunities to apply chemistry knowledge in the chemistry lab exercises, detailed procedures for the simulated laboratory exercises, the organization of the course Blackboard sites and the chemistry lab simulation web sites, and the textbook homework web sites. Students also identified components of instructional support they felt were missing. These included a desire for more interaction with the instructor, more support for the simulated laboratory exercises from the instructor and the developer of the chemistry simulations, and faster help with questions about the laboratory exercises or experimental calculations. Students believed that having this additional instructional support would lead to increased understanding of the laboratory exercises, allowing them to complete them with less difficulty, and giving them increased access to the instructor. Recommendations for the instructors of these two courses include: increased participation in the online course environment, increased emphasis on laboratory safety, and increased emphasis on the differences between simulated and real life chemistry laboratory experiments.

Schulman, Kathleen M.

248

A chamber for laboratory studies of atmospheric aerosols and clouds  

NASA Astrophysics Data System (ADS)

A stainless-steel chamber has been constructed and interfaced to a Fourier transform infrared spectrometer for the purpose of studying laboratory simulated atmospheric aerosols and clouds. The chamber is cylindrical in design and is comprised of a double-walled inner assembly that resides within an outer vacuum jacket. The volume of the aerosol sample region is 28 L. By circulating refrigerated methanol between the double walls of the inner assembly, constant temperature control of the sample region can be maintained between 187 and 300 K. A study of temperature uniformity within the chamber at 291, 240, and 187 K revealed a standard deviation in temperature of 1.6 K as determined from measurements made using five copper-constantan thermocouples. Good agreement is obtained between thermocouple measured temperatures and rotational temperatures computed from infrared absorption spectra of methane gas. The chamber described here has been used to examine heterogeneous chemistry of solid powder samples. A technique of generating an aerosol sample by rapidly dispersing a solid powder in a gas is presented. The half-life of a ?-alumina aerosol sample was measured to be 25 min.

Narus, M. L.; Schoenfelder, N. C.; Na, Y.; Chavasse, L. A.; Disselkamp, R. S.

1996-12-01

249

Synthetic cathinones and their rewarding and reinforcing effects in rodents  

PubMed Central

Synthetic cathinones, colloquially referred to as “bath salts”, are derivatives of the psychoactive alkaloid cathinone found in Catha edulis (Khat). Since the mid-to-late 2000’s, these amphetamine-like psychostimulants have gained popularity amongst drug users due to their potency, low cost, ease of procurement, and constantly evolving chemical structures. Concomitant with their increased use is the emergence of a growing collection of case reports of bizarre and dangerous behaviors, toxicity to numerous organ systems, and death. However, scientific information regarding the abuse liability of these drugs has been relatively slower to materialize. Recently we have published several studies demonstrating that laboratory rodents will readily self-administer the “first generation” synthetic cathinones methylenedioxypyrovalerone (MDPV) and methylone via the intravenous route, in patterns similar to those of methamphetamine. Under progressive ratio schedules of reinforcement, the rank order of reinforcing efficacy of these compounds are MDPV ? methamphetamine > methylone. MDPV and methylone, as well as the “second generation” synthetic cathinones ?-pyrrolidinovalerophenone (?-PVP) and 4-methylethcathinone (4-MEC), also dose-dependently increase brain reward function. Collectively, these findings indicate that synthetic cathinones have a high abuse and addiction potential and underscore the need for future assessment of the extent and duration of neurotoxicity induced by these emerging drugs of abuse. PMID:25328910

Watterson, Lucas R.; Olive, M. Foster

2014-01-01

250

Diversity of gastrointestinal helminths among murid rodents from northern and northeastern Thailand.  

PubMed

The presence of gastrointestinal helminths (GI helminths) was investigated among 725 murid rodents, trapped in various habitats of Nan, Loei and Buri Ram Provinces, Thailand. The study revealed 17 species of rodents infected with 21 species or taxonomic groups of parasites (3 trematodes, 3 cestodes, 14 nematodes and 1 acanthocephalan). The overall prevalence of infection was 57.7% (418/725). Of the gastrointestinal (GI) helminths, the dominant parasitic group was members of the family Trichostrongylidae (24.3%), followed by the cestodes Raillietina sp (17.1%) and Hymenolepis diminuta (8.6%) and the nematode Syphacia muris (8.6%). The GI helminthic infection rates were highest in Mus caroli (81.8%), Mus cervicolor (76.5%), Leopoldamys edwardsi (75.0%), Bandicota indica (71.5%) and Bandicota savilei (71.4%). Highest rodent species richness (RSR) and helminth species richness (HSR) rates were found in Loei, followed by Nan and Buri Ram. The helminth prevalence rate was higher in rodents from Nan, followed by rodents from Loei and Buri Ram. Rodents from irrigated fields had the highest infection rates followed by rodents from upland or dry agricultural areas, forests and domestic habitats. Raillietina sp, Rodentolepis nana (syn. Hymenolepis nana), Hymenolepis diminuta, Moniliformis moniliformis and Cyclodontostomum purvisi, considered zoonotic parasites, were mainly found in rodents from domestic habitats and lowland irrigated fields. PMID:23082550

Chaisiri, Kittipong; Chaeychomsri, Win; Siruntawineti, Jindawan; Ribas, Alexis; Herbreteau, Vincent; Morand, Serge

2012-01-01

251

Anti-erosion stone bunds influence rodent dynamics and crop damage in Ethiopian highlands  

NASA Astrophysics Data System (ADS)

In areas of subsistence agriculture, a variety of soil conservation methods have been implemented in the last few decades to improve crop yields, however these can have unintended consequences such as providing habitat for rodent pests. We studied rodent population dynamics and estimated crop damage in high and low stone bund density fields for four cropping seasons in Tigray highlands, northern Ethiopia. Stone bunds are physical structures for soil and water conservation, and potentially habitat for rodents. We used a general model to relate the proportion of crop damage to rodent abundance, stone bund density and crop stages. We found a positive correlation between rodent abundance and crop damage, and significant variation in rodent abundance and crop damage between high and low stone bund density fields. Furthermore, crop damage also varied significantly between crop stages. We concluded that Mastomys awashensis and Arvicanthis dembeensis were the two most important crop pests in the highlands causing significant damage. Fields with high stone bund density (~10 m average distance apart) harbor more rodents and endure a significantly higher proportion of crop damage compared to fields with lower stone bund density (~15 m average distance apart). The fact that rodent abundances peaked during the reproductive stage of the crop and around harvest implies the need for management intervention before these crop stages are attained.

Meheretu, Yonas; Welegerima, Kiros; Teferi, Mekonen; Yirga, Gidey; Haile, Mitiku; Sluydts, Vincent; Bauer, Hans; Nyssen, Jan; Deckers, Jozef; Leirs, Herwig

2014-05-01

252

Interspecific competition in small rodents: from populations to individuals  

Microsoft Academic Search

The role of interspecific competition in shaping animal and plant communities has formed one of the major issues in ecology for decades. Small mammals, mainly rodents, have been among the model systems used for research on interspecific competition. Most studies within small mammal systems in the past have examined effects of competition on population attributes such as on population size,

Jana A. Eccard; Hannu Ylönen

2003-01-01

253

Andes Hantavirus Variant in Rodents, Southern Amazon Basin, Peru  

PubMed Central

We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted. PMID:24447689

Tokarz, Rafal; Ghersi, Bruno M.; Salmon-Mulanovich, Gabriela; Guezala, M. Claudia; Albujar, Christian; Mendoza, A. Patricia; Tinoco, Yeny O.; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah; Nichol, Stuart T.; Hirschberg, David L.; Lipkin, W. Ian; Bausch, Daniel G.; Montgomery, Joel M.

2014-01-01

254

Urban resident attitudes toward rodents, rodent control products, and environmental effects  

EPA Science Inventory

Rodent control in urban areas can result in the inadvertent mortality of non-target species (e.g., bobcats). However, there is little detailed information about rodent control practices of urban residents. Our objective was to evaluate urban rodent control behaviors in two area...

255

Factors determining the abundance and distribution of rodents in a shrub-steppe ecosystem: the role of shrubs  

Microsoft Academic Search

This study addressed the relative importances of shrub “resources” on a rodent community in a sagebrush dominated shrub-steppe ecosystem in southwestern Wyoming. Direct effects of shrubs (i.e., providing rodents with “food and cover”) were assessed by removing shrubs from a 1.25 ha study plot and monitoring both rodent populations and their food resources. Shrub architecture and shrub-related food resources were

Robert R. Parmenter; James A. MacMahon

1983-01-01

256

B chromosomes in Brazilian rodents.  

PubMed

B chromosomes are now known in eight Brazilian rodent species: Akodon montensis, Holochilus brasiliensis, Nectomys rattus, N. squamipes, Oligoryzomys flavescens, Oryzomys angouya, Proechimys sp. 2 and Trinomys iheringi. Typically these chromosomes are heterogeneous relative to size, morphology, banding patterns, presence/absence of NORs, and presence/absence of interstitial telomeric signals after FISH. In most cases, Bs are heterochromatic and late replicating. Active NORs were detected in two species: Akodon montensis and Oryzomys angouya. As a rule, Bs behave as uni or bivalents in meiosis, there is no pairing between Bs and autosomes or sex chromosomes and also their synaptonemal complexes are isopycnotic with those in A chromosomes. PMID:15292600

Silva, M J J; Yonenaga-Yassuda, Y

2004-01-01

257

DNA vaccines for HFRS: laboratory and clinical studies.  

PubMed

DNA vaccines can be constructed to produce specific immunogens while avoiding the risks associated with propagating infectious viruses. Plasmid DNA vaccines have well established manufacturing procedures and are safe in that they are replication defective, cannot revert to virulence and cannot be transmitted from person-to-person or into the environment. In addition, DNA vaccines can be combined to form multivalent formulations and can be delivered by a variety of methods. Because of these numerous advantages, we have developed DNA vaccines expressing the envelope glycoprotein genes of hantaviruses causing hemorrhagic fever with renal syndrome (HFRS). We have demonstrated that these DNA vaccines elicit neutralizing antibodies in multiple laboratory animal species when delivered to skin or muscle tissues. Moreover, these vaccines delivered as active vaccines or passive vaccines (e.g., transfer of sera from vaccinated rabbits or nonhuman primates), protected hamsters from infection with HFRS-causing hantaviruses. Early clinical studies of HFRS vaccines expressing Hantaan virus or Puumala virus genes have been completed and show promise for further development. Despite these advantages, issues relating to inconsistent immunogenicity and immune interference remain to be addressed. PMID:24370868

Schmaljohn, Connie S; Spik, Kristin W; Hooper, Jay W

2014-07-17

258

ER-2: Flying Laboratory for Earth Science Studies  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) Dryden Flight Research Center (DFRC), (Edwards, California, USA) has two Lockheed Martin Corporation (Bethesda, Maryland) Earth Research-2 (ER-2) aircraft that serve as high-altitude and long-range flying laboratories. The ER-2 has been utilized to conduct scientific studies of stratospheric and tropospheric chemistry, land-use mapping, disaster assessment, preliminary testing and calibration and validation of satellite sensors. The ER-2 aircraft provides experimenters with a wide array of payload accommodation areas with suitable environment control with required electrical and mechanical interfaces. Missions may be flown out of DFRC or from remote bases worldwide. The NASA ER-2 is utilized by a variety of customers, including U.S. Government agencies, civilian organizations, universities, and state governments. The combination of the ER-2 s range, endurance, altitude, payload power, payload volume and payload weight capabilities complemented by a trained maintenance and operations team provides an excellent and unique platform system to the science community.

Navarro, Robert

2007-01-01

259

Robust Reproducible Resting State Networks in the Awake Rodent Brain  

PubMed Central

Resting state networks (RSNs) have been studied extensively with functional MRI in humans in health and disease to reflect brain function in the un-stimulated state as well as reveal how the brain is altered with disease. Rodent models of disease have been used comprehensively to understand the biology of the disease as well as in the development of new therapies. RSN reported studies in rodents, however, are few, and most studies are performed with anesthetized rodents that might alter networks and differ from their non-anesthetized state. Acquiring RSN data in the awake rodent avoids the issues of anesthesia effects on brain function. Using high field fMRI we determined RSNs in awake rats using an independent component analysis (ICA) approach, however, ICA analysis can produce a large number of components, some with biological relevance (networks). We further have applied a novel method to determine networks that are robust and reproducible among all the components found with ICA. This analysis indicates that 7 networks are robust and reproducible in the rat and their putative role is discussed. PMID:22028788

Becerra, Lino; Pendse, Gautam; Chang, Pei-Ching; Bishop, James; Borsook, David

2011-01-01

260

Protein composition of the ventral processes on the sperm head of Australian hydromyine rodents.  

PubMed

The sperm head of the plains rat, an Australian hydromyine rodent, is highly complex in structure and contains, in addition to an apical hook, two large ventral processes (VPs) that extend from its upper concave surface and that are largely composed of a huge extension of the sperm head cytoskeleton surrounded by postacrosomal dense lamina. In this study we have attempted to determine their protein composition. For this, the VPs were isolated, the proteins within them separated by SDS-PAGE, and the resultant polypeptide bands Western blotted and probed with antibodies against laboratory rat perforatorial and bull perinuclear theca sperm proteins. Antibodies were also used to determine the perforatorial and perinuclear theca proteins by immunogold labeling of transmission electron microscopic sections. The results indicate that the material within the VPs is largely composed of perforatorial cross-reacting proteins together with F-actin with the dominant protein being PERF 15. The perinuclear theca proteins are, by contrast, restricted to a narrow region adjacent to the acrosomal and nuclear membranes. In conclusion, this study has shown that the VPs of the spermatozoa of Australian rodents are perforatorial-like appendages that contain similar proteins to the perforatorium of the apical hook together with F-actin; their functional significance remains unknown. PMID:10906074

Breed, W G; Idriss, D; Oko, R J

2000-08-01

261

Next-Generation Sequencing for Rodent Barcoding: Species Identification from Fresh, Degraded and Environmental Samples  

PubMed Central

Rodentia is the most diverse order among mammals, with more than 2,000 species currently described. Most of the time, species assignation is so difficult based on morphological data solely that identifying rodents at the specific level corresponds to a real challenge. In this study, we compared the applicability of 100 bp mini-barcodes from cytochrome b and cytochrome c oxidase 1 genes to enable rodent species identification. Based on GenBank sequence datasets of 115 rodent species, a 136 bp fragment of cytochrome b was selected as the most discriminatory mini-barcode, and rodent universal primers surrounding this fragment were designed. The efficacy of this new molecular tool was assessed on 946 samples including rodent tissues, feces, museum samples and feces/pellets from predators known to ingest rodents. Utilizing next-generation sequencing technologies able to sequence mixes of DNA, 1,140 amplicons were tagged, multiplexed and sequenced together in one single 454 GS-FLX run. Our method was initially validated on a reference sample set including 265 clearly identified rodent tissues, corresponding to 103 different species. Following validation, 85.6% of 555 rodent samples from Europe, Asia and Africa whose species identity was unknown were able to be identified using the BLASTN program and GenBank reference sequences. In addition, our method proved effective even on degraded rodent DNA samples: 91.8% and 75.9% of samples from feces and museum specimens respectively were correctly identified. Finally, we succeeded in determining the diet of 66.7% of the investigated carnivores from their feces and 81.8% of owls from their pellets. Non-rodent species were also identified, suggesting that our method is sensitive enough to investigate complete predator diets. This study demonstrates how this molecular identification method combined with high-throughput sequencing can open new realms of possibilities in achieving fast, accurate and inexpensive species identification. PMID:23144869

Galan, Maxime; Pagès, Marie; Cosson, Jean-François

2012-01-01

262

A laboratory study of the friction behavior of granular materials  

E-print Network

I report on laboratory experiments designed to investigate the microphysical processes that result in rate- and state-dependent friction behavior and experiments designed to match the boundary conditions used by numerical ...

Frye, Kevin M. (Kevin Michael), 1972-

2002-01-01

263

Case Study- Steam System Improvements at Dupont Automotive Marshall Laboratory  

E-print Network

Dupont's Marshall Laboratory is an automotive paint research and development facility in Philadelphia, Pennsylvania. The campus is comprised of several buildings that are served by Trigen-Philadelphia Energy Corporation's district steam loop...

Larkin, A.

264

The Study of a Cobalt Complex--A Laboratory Project.  

ERIC Educational Resources Information Center

Describes an 8-week project involving the synthesis of cobalt compounds. Once synthesized, compounds are qualitatively and quantitatively analyzed. Background information, laboratory procedures, and results/discussion are provided for three project experiments. (Author/JN)

Loehlin, James H.; And Others

1982-01-01

265

Infrared studies at the ice laboratory of Alcoy  

Microsoft Academic Search

At present, there are few laboratory spectra of analogs of astrophysical interest in the far-infrared range (FIR). Laboratory infrared (IR) spectra of simple ices and its mixtures obtained at low temperature and pressure are found mainly up to 25?m, and few up to 200?m. On the other hand, there are some spectra for carbonaceous material and silicates up to 2000?m.

R. Vilaplana; O. Gomis; R. Luna; J. Cantó

2008-01-01

266

Single media thermocline TES studies at Sandia National Laboratories  

SciTech Connect

The status of thermocline thermal energy storage (TES) development at Sandia National Laboratories is summarized. The work centers around testing in the 1200 gal engineering prototype thermocline test facility. The results of heat loss, charge, discharge and static tests in the prototype tank are described. Also described are analytical work and a supportive laboratory-scale program which is investigating diffusers to inhibit mixing in the tank.

Gross, R.J.

1981-01-01

267

20 CFR 654.415 - Insect and rodent control.  

...2014-04-01 2014-04-01 false Insect and rodent control. 654.415 Section...Workers Housing Standards § 654.415 Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other...

2014-04-01

268

20 CFR 654.415 - Insect and rodent control.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Insect and rodent control. 654.415 Section...Workers Housing Standards § 654.415 Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other...

2012-04-01

269

20 CFR 654.415 - Insect and rodent control.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Insect and rodent control. 654.415 Section...Workers Housing Standards § 654.415 Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other...

2013-04-01

270

20 CFR 654.415 - Insect and rodent control.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Insect and rodent control. 654.415 Section...Workers Housing Standards § 654.415 Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other...

2011-04-01

271

20 CFR 654.415 - Insect and rodent control.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Insect and rodent control. 654.415 Section...Workers Housing Standards § 654.415 Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other...

2010-04-01

272

Laboratory studies of imitation/field studies of tradition: Towards a synthesis in animal social learning.  

PubMed

Here I discuss: (1) historical precedents that have resulted in comparative psychologists accepting the two-action method as the "gold standard" in laboratory investigations of imitation learning, (2) evidence suggesting that the two-action procedure may not be adequate to answer questions concerning the role of imitation in the development of traditional behaviors of animals living in natural habitat, and (3) an alternative approach to the laboratory study of imitation that might increase the relevance of laboratory studies of imitation to the work of behavioral ecologists/primatologists interested in animal traditions and their relationship to human cumulative culture. This article is part of a Special Issue entitled: Tribute to Tom Zentall. PMID:25058622

Galef, Bennett G

2015-03-01

273

Los Alamos National Laboratory W76 Pit Tube Lifetime Study  

SciTech Connect

A metallurgical study was requested as part of the Los Alamos National Laboratory (LANL) W76-1 life-extension program (LEP) involving a lifetime analysis of type 304 stainless steel pit tubes subject to repeat bending loads during assembly and disassembly operations at BWXT/Pantex. This initial test phase was completed during the calendar years of 2004-2006 and the report not issued until additional recommended tests could be performed. These tests have not been funded to this date and therefore this report is considered final. Tubes were reportedly fabricated according to Rocky Flats specification P14548 - Seamless Type 304 VIM/VAR Stainless Steel Tubing. Tube diameter was specified as 0.125 inches and wall thickness as 0.028 inches. A heat treat condition is not specified and the hardness range specification can be characteristic of both 1/8 and 1/4 hard conditions. Properties of all tubes tested were within specification. Metallographic analysis could not conclusively determine a specified limit to number of bends allowable. A statistical analysis suggests a range of 5-7 bends with a 99.95% confidence limit. See the 'Statistical Analysis' section of this report. The initial phase of this study involved two separate sets of test specimens. The first group was part of an investigation originating in the ESA-GTS [now Gas Transfer Systems (W-7) Group]. After the bend cycle test parameters were chosen (all three required bends subjected to the same amount of bend cycles) and the tubes bent, the investigation was transferred to Terri Abeln (Metallurgical Science and Engineering) for analysis. Subsequently, another limited quantity of tubes became available for testing and were cycled with the same bending fixture, but with different test parameters determined by T. Abeln.

Abeln, Terri G. [Los Alamos National Laboratory

2012-04-25

274

Assessment of the use of selected rodents in ecological monitoring  

NASA Astrophysics Data System (ADS)

Rodents can be useful in detecting environmental impacts because they are easy to study (easy to capture and handle), they can occur in densities adequate for statistical analysis, and they are ecologically important. In this study the usefulness of rodent populations for ecological monitoring was investigated by examining the effect of variation on the possibility of detecting differences among populations of rodents on 10 trapping grids. The effects of sampling frequencies and dispersal on detecting differences in population parameters among grids was also investigated, as was the possibility of inferring population parameters from correlations with habitat data. Statistically significant differences as small as 4.3 Peromyscus maniculatus/ha were detected between grids. Of 10 populations, this comprised 12% of the highest-density population and 44% of the lowest-density population. Smaller and more differences among grids were found by examining only animals surviving from previous months. Dispersal confounds detection of direct impacts to populations, especially during the breeding season. Infrequent sampling fails to detect impacts that occur between sampling periods and will indicate impacts when observed changes result from natural variation. Correlations between population parameters and habitat variables exist but should only be used in predicting, not measuring, impacts. It is concluded that some rodent populations can be used in ecological monitoring. However, intensive sampling is required to account for variation and dispersal.

Douglass, Richard J.

1989-05-01

275

COMPARISON OF FIELD- AND LABORATORY-DEVELOPED ESTUARINE BENTHIC COMMUNITIES FOR TOXICANT-EXPOSURE STUDIES  

EPA Science Inventory

The structures of macrobenthic communities that colonized sand-filled boxes in laboratory and field were compared to learn if laboratory-developed assemblages of animals used in toxicity studies realistically simulate those in nature. Laboratory boxes were colonized for eight wee...

276

Phosphate release from seasonally flooded soils: a laboratory microcosm study.  

PubMed

Phosphorus derived from agricultural practices has been targeted as a leading cause of water quality degradation in Lake Champlain. Mobilization of P from seasonally flooded agricultural soils is a concern. Using 14 soils from a research farm in New York's Champlain Valley, we characterized the available P status, extractable Fe and Al, P sorption capacities, and soluble phosphate release in flooded laboratory microcosms. Quantities of NH4-acetate available P ranged from 3 to 100 mg kg(-1) and fluoride-extractable P from 10 to 211 mg kg(-1). Flooding soils induced significant release of phosphate to the porewater over a 60- to 90-d period in 13 of the 14 soils studied. Porewater phosphate increases ranged from 2.2 to 27.0 times the initial phosphate concentrations. However, floodwater phosphate increases were much lower, with a maximum of 3.6 times the initial concentration. Average porewater phosphate concentrations over the flooding period ranged from 0.046 to 7.0 mg L(-1) and average floodwater P from 0.032 to 3.70 mg L(-1). Ammonium-acetate P and the degree of phosphorus saturation (DPS) were highly correlated with the average porewater and floodwater phosphate concentration. Average ratio of porewater to floodwater phosphate concentrations ranged from 1.0 to 3.3. Five soils that were lower in fluoride-extractable P had increasing porewater phosphate accompanied by increasing porewater Fe2+ and decreasing floodwater phosphate. Results suggest that P solubility and mobility were a function of both the available P status and redox cycling. PMID:11215671

Young, E O; Ross, D S

2001-01-01

277

Laboratory Study of Angular Momentum Transport in Sheared Rotating Flows  

NASA Astrophysics Data System (ADS)

Rapid angular momentum transport in accretion disks is a longstanding astrophysical puzzle. Transport by molecular viscosity is inadequate to explain observationally inferred accretion rates. Since Keplerian flows are linearly stable in hydrodynamics, there exist only two main viable mechanisms for the required turbulence: nonlinear hydrodynamic instability or linear magnetorotational instability (MRI). The latter is regarded as a dominant mechanism for rapid angular momentum transport in hot accretion disks ranging from quasars and X-ray binaries to cataclysmic variables. The former is proposed mainly for cooler protoplanetary disks, whose Reynolds numbers are typically large. Despite their popularity, however, there is limited experimental evidence for either mechanism. In this talk, I will describe a laboratory experiment at Princeton (http://mri.pppl.gov) in a short Taylor-Couette flow geometry intended to study these mechanisms. Based on the results from prototype experiments and simulations, the apparatus contains novel features for better controls of the boundary-driven secondary flows. The experiments in water have shown1 that nonmagnetic quasi-Keplerian flows at Reynolds numbers as large as 2× 106 are essentially laminar, through means of direct measurements of Reynolds stress via a synchronized, dual Laser Doppler Velocimetry. Scaled to accretion disks, rates of angular momentum transport lie far below astrophysical requirements. By ruling out hydrodynamic turbulence, our results indirectly support MRI as the likely cause of turbulence even in cool disks. The experiments in liquid gallium eutectic alloy have recently begun, and initial results on MRI as well as other related phenomena including numerical predictions will be also discussed if available. 1. H. Ji, M. Burin, E. Schartman, & J. Goodman, Nature 444, 343-346 (2006).

Ji, Hantao; Nornberg, M.; Schartman, E.; Goodman, J.; Liu, W.; Roach, A.

2008-05-01

278

A laboratory study of radiation damage to drift chambers  

NASA Astrophysics Data System (ADS)

A laboratory study of aging effects under intense radiation in Ar/C 2H 6 and Ar/CO 2/CH 4 filled drift chambers was carried out in order to establish detector lifetimes. In both gas mixtures stable operation in proportional mode and for Ar/C 2H 6 also in the limited streamer regime was possible up to total collected charges of several times 10 17 e - per mm of anode wire. Gain reductions were observed at rates between 0 and 1% per 10 16 e -/mm for Ar/C 2H 6 depending on the test conditions. Under conditions, where gas amplification was stable in Ar/C 2H 6, gain losses in Ar/CO 2/CH 4 ranged between 1.3 and 3.4% per 10 16 e -/mm. Gain nonuniformities were inferred from broadenings and distortions of the 55Fe 5.9 keV ? line. These gain variations are caused by typically less than 100 nm thick deposits on the aged anode wires of poorly conductive material containing O, Si and C. Admixtures of H 2O did not halt the aging processes, but smoothed local gain variations. Contaminations with organic vapor from soft PVC surfaces initiated and accelerated radiation damage. Spark and glow discharges in Ar/C 2H 6 led to growth of grains and flakes of material containing C as the only detectable element on anode and cathode wires within minutes. In contrast discharges in Ar/CO 2CH 4 did not result in any detectable deposits.

Kotthaus, Rainer

1986-12-01

279

[Laboratory and clinical studies of cefpodoxime proxetil in pediatric field].  

PubMed

We have carried out laboratory and clinical studies on cefpodoxime proxetil (CS-807, CPDX-PR). The results are summarized as follows. CPDX-PR was given via oral administration to each 2 children at a single dose of 3 mg/kg and to each of 3 children in a 100 mg tablet. After the oral administration, mean peak serum levels of CPDX obtained for the 2 dose levels were 1.86 +/- 0.35 micrograms/ml and 2.16 +/- 0.63 micrograms/ml at 2 hours, respectively, and mean half-lives were 1.31 +/- 0.02 hours and 1.47 +/- 0.18 hours, respectively. The mean urinary excretion rate of CPDX was 32.8 +/- 1.0% in the first 12 hours after the oral administration of 3 mg/kg. When a dose of 100 mg tablet was given to each of the 3 children, urinary excretion rates in the first 12 hours were 43.5%, 48.6% and 24.8%, respectively. Treatment with CPDX-PR was done in 38 cases of pediatric bacterial infections; 19 cases of tonsillitis, 3 cases of pharyngitis, 1 case of bronchitis, 3 cases of pneumonia, 3 cases of scarlet fever, 2 cases of impetigo, 4 cases of UTI and 1 case each of phlegmone, subcutaneous abscess and balanitis. Results obtained were excellent in 23 cases, good in 15 cases. No significant side effect due to the drug was observed in any cases. PMID:2810732

Nishimura, T; Tabuki, K; Aoki, S; Takagi, M

1989-07-01

280

Rodent Models for Metabolic Syndrome Research  

PubMed Central

Rodents are widely used to mimic human diseases to improve understanding of the causes and progression of disease symptoms and to test potential therapeutic interventions. Chronic diseases such as obesity, diabetes and hypertension, together known as the metabolic syndrome, are causing increasing morbidity and mortality. To control these diseases, research in rodent models that closely mimic the changes in humans is essential. This review will examine the adequacy of the many rodent models of metabolic syndrome to mimic the causes and progression of the disease in humans. The primary criterion will be whether a rodent model initiates all of the signs, especially obesity, diabetes, hypertension and dysfunction of the heart, blood vessels, liver and kidney, primarily by diet since these are the diet-induced signs in humans with metabolic syndrome. We conclude that the model that comes closest to fulfilling this criterion is the high carbohydrate, high fat-fed male rodent. PMID:21253582

Panchal, Sunil K.; Brown, Lindsay

2011-01-01

281

Dissociative Electron Attachment to Hydrocarbons. A Laboratory Study  

NASA Astrophysics Data System (ADS)

Laboratory studies of PAHs continue to be essential if we are to interpret the wealth and variety of processes contributing to star formation. In the realm of gas-phase kinetics reactions involving negative ions are being studied to help modellers understand the role of these species in interstellar chemistry. Observations have shown that PAHs molecules are abundant and ubiquitous in the interstellar medium of galaxies, play an important role in its physical and chemical characteristics and form a key link between small hydrocarbon species and large carbonaceous grains. There is therefore considerable interest in the mechanisms by which these molecules and their anions may form. One method is electron induced chemistry within the icy mantles on the surface of dust grains. In particular it has been recently shown that functional group dependence exists in electron attachment processes giving rise to site selective fragmentation of molecules at the C-H, O-H and N-H bonds at energies well beyond the threshold for the breaking of any of these bonds allowing novel forms of chemistry that have little or no activation barriers, such as are necessary in the ISM. In this poster we present the results of recent studies on dissociative electron attachment (DEA) to PAHs using an improved version of a Velocity Map Imaging (VMI) spectrometer comprised of a magnetically collimated and low energy pulsed electron gun, a Faraday cup, an effusive molecular beam, a pulsed field ion extraction, a time of flight analyzer and a two-dimensional position sensitive detector consisting of microchannel plate and a phosphor screen. The VMI spectrometer measures the kinetic energy and angular distribution of the fragment anions produced in the dissociative electron attachment process. Kinetic energy measurements provide information on the internal energies of the fragment anions and determine the dissociation limits of the parent negative ion resonant states responsible for the dissociative electron attachment process. Angular distribution measurements provide information about the symmetry of these negative ion resonant states. We shall present the details, results and conclusions of these measurements during the conference for some illustrative hydrocarbons.

Szymanska, E.; Mason, N. J.

2011-05-01

282

Latitudinal patterns in rodent metabolic flexibility.  

PubMed

Macrophysiology is defined as the study of variation in physiological traits-including physiological trait flexibility-over large geographical and temporal scales, and the ecological implications of this variation. A classic example of a macrophysiological trend is the one emerging from the climatic variability hypothesis, which states that as the range of climatic fluctuation experienced by terrestrial animals increases with latitude, individuals at higher latitudes should be more plastic than individuals inhabiting lower latitudes. In this context, we evaluate the correlation between absolute metabolic scope during cold exposure (an instantaneous measure of metabolic flexibility) and different geographic and climatic variables for 48 rodent species. Conventional and phylogenetic informed analyses indicated a positive correlation between metabolic scope and geographic latitude. These findings, together with previous reports on latitudinal pattern in phenotypic flexibility, suggest that an increase in physiological flexibility with latitude may hold for many phenotypic traits. PMID:22617269

Naya, Daniel E; Spangenberg, Lucia; Naya, Hugo; Bozinovic, Francisco

2012-06-01

283

Assessing Spatial Learning and Memory in Rodents  

PubMed Central

Maneuvering safely through the environment is central to survival of almost all species. The ability to do this depends on learning and remembering locations. This capacity is encoded in the brain by two systems: one using cues outside the organism (distal cues), allocentric navigation, and one using self-movement, internal cues and nearby proximal cues, egocentric navigation. Allocentric navigation involves the hippocampus, entorhinal cortex, and surrounding structures; in humans this system encodes allocentric, semantic, and episodic memory. This form of memory is assessed in laboratory animals in many ways, but the dominant form of assessment is the Morris water maze (MWM). Egocentric navigation involves the dorsal striatum and connected structures; in humans this system encodes routes and integrated paths and, when overlearned, becomes procedural memory. In this article, several allocentric assessment methods for rodents are reviewed and compared with the MWM. MWM advantages (little training required, no food deprivation, ease of testing, rapid and reliable learning, insensitivity to differences in body weight and appetite, absence of nonperformers, control methods for proximal cue learning, and performance effects) and disadvantages (concern about stress, perhaps not as sensitive for working memory) are discussed. Evidence-based design improvements and testing methods are reviewed for both rats and mice. Experimental factors that apply generally to spatial navigation and to MWM specifically are considered. It is concluded that, on balance, the MWM has more advantages than disadvantages and compares favorably with other allocentric navigation tasks. PMID:25225309

Vorhees, Charles V.; Williams, Michael T.

2014-01-01

284

A Study of the Effectiveness of the Instructional Systems Laboratory.  

ERIC Educational Resources Information Center

A survey examined perception and use of the services of the Instructional Systems Laboratory (ISL) by the faculty of the University of Minnesota's College of Education. The questionnaire, mailed to all College of Education faculty members, emphasized faculty perception of instructional systems in the following areas: (1) instructional commitment:…

Philipson, Will D.; Chan-Tam, Pik Wai

285

Ions, isotopes, and metal cyanides: Observational and laboratory studies  

NASA Astrophysics Data System (ADS)

Chemistry in the interstellar medium is very different from the processes which take place in terrestrial settings. Environments such as circumstellar envelopes, molecular clouds, and comets contain diverse and complex chemical networks. The low temperatures (10 50 K) and densities (1 10 6 cm-3) allow normally unstable molecules to exist in significant quantities. At these temperatures, the rotational energy levels of molecules are populated, and thus these species can be detected by millimeter-wave radio astronomy. The detection and quantification of interstellar molecules, including metal cyanides and molecular ions, is the basis of this dissertation work. While conducting observations of CN and 13CN to determine the 12C/13C ratio throughout the Galaxy, it was found that the ratios in photon- dominated regions (PDRs) were much higher than those in nearby molecular clouds. This can be explained by isotope-selective photodissociation, in which the 12CN molecules are self-shielded. However, the chemistry in these regions is poorly understood, and other processes may be occurring. In order to understand one of the chemical networks present in PDRs, observations of HCO+, HOC +, and CO+ were made toward several of these sources. Previous studies indicated that the HCO+/HOC+ ratio was much lower in PDRs, due to the presence of CO+. The new observations indicate that there is a strong correlation between CO + and HOC+ abundances, which suggests that other molecular ions which have not been detected in molecular clouds may be present in PDRs. There is a significant obstacle to the detection of new interstellar molecular ions, however. The laboratory spectra are virtually unknown for many of these species, due to their inherent instability. Thus, techniques which can selectively detect ionic spectra must be utilized. One such method is velocity modulation, which incorporates an AC electrical discharge to produce and detect ions. Previously, velocity modulation spectroscopy was employed only at infrared wavelengths. The final phase of this dissertation work was to design, build and test a velocity modulation spectrometer which functions at millimeter/sub-mm wavelengths. This system was then used to measure the previously unknown pure rotational spectrum of SH+ (X3E- ).

Savage, Chandra Shannon

2004-11-01

286

Snapshot PK: a rapid rodent in vivo preclinical screening approach.  

PubMed

Described in this article are strategies implemented to increase the throughput of in vivo rodent pharmacokinetic (PK) studies using the snapshot PK study design and automated methods for compound submission, sample processing, data analysis and reporting. Applying snapshot PK studies to categorize the oral exposure of >1300 discovery compounds as low, moderate or high resulted in an attrition rate of 86%. The follow up full PK studies on the remaining compounds found that 98% of the compounds were predicted in the correct (69%) or adjacent (29%) oral exposure category by the snapshot PK studies. These results demonstrate that the snapshot PK screen in rodents can serve as an effective and efficient in vivo tool in the compound selection process in drug discovery. PMID:18405850

Liu, Bo; Chang, Jonathan; Gordon, William P; Isbell, John; Zhou, Yingyao; Tuntland, Tove

2008-04-01

287

Acute and chronic toxicity of a lyophilised aqueous extract of Tanacetum vulgare leaves in rodents  

Microsoft Academic Search

Aim of the studyThe present investigation was carried out to evaluate the safety of an aqueous extract of tansy (Tanacetum vulgare L.) leaves by determining its potential toxicity after acute and chronic administration in rodents.

Sanaa Lahlou; Zafar H. Israili; Badiâa Lyoussi

2008-01-01

288

COMPARATIVE MICROARRAY EXPRESSION ANALYSIS OF SELECTED CANCER RELEVANT GENES IN HYPERTENSIVE RESISTANT VERSUS SUSCEPTIBLE RODENT STRAINS  

EPA Science Inventory

Hypertension and cancer are prevalent diseases. Epidemiological studies suggest that hypertension may increase the long term risk of cancer. Identification of resistance and/or susceptibility genes using rodent models could provide important insights into the management and treat...

289

Adaptation in Rodent Moles and Insectivorous Moles, and the Theory of Convergence  

Microsoft Academic Search

STUDIES in connexion with the life-history of the Orange Free State rodent mole, Cryptomys, brought to light a remarkable degree of adaptation, anatomically and psychologically, to its mode of life in total darkness.

G. Eloff

1951-01-01

290

Anti-dementia drugs and hippocampal-dependent memory in rodents  

PubMed Central

Abnormalities in hippocampal structure and function are characteristics of early Alzheimer's disease (AD). Behavioral tests measuring hippocampal-dependent memory in rodents are often used to evaluate novel treatments for AD and other dementias. In this study, we review the effects of drugs marketed for the treatment of AD, such as the acetylcholinesterase inhibitors, donepezil, rivastigmine, galantamine and the N-methyl-d-aspartic acid antagonist, memantine, in rodent models of memory impairment. We also briefly describe the effects of novel treatments for cognitive impairment in rodent models of memory impairment, and discuss issues concerning the selection of the animal model and behavioral tests. Suggestions for future research are offered. PMID:17762506

Yuede, Carla M.; Dong, Hongxin; Csernansky, John G.

2009-01-01

291

Recent Expansion of the Telomeric Complex in Rodents: Two Distinct POT1  

E-print Network

Recent Expansion of the Telomeric Complex in Rodents: Two Distinct POT1 Proteins Protect Mouse Telomeres Dirk Hockemeyer,1 Jan-Peter Daniels,1 Hiroyuki Takai,1 and Titia de Lange1, * 1 Laboratory *Contact: delange@mail.rockefeller.edu DOI 10.1016/j.cell.2006.04.044 SUMMARY Human telomeres are protected

de Lange, Titia

292

Office of the Vice President for Research UGA IACUC Policy on Rodent Euthanasia using Carbon Dioxide  

E-print Network

Office of the Vice President for Research UGA IACUC Policy on Rodent Euthanasia using Carbon Dioxide Approved by UGA IACUC Revised 22014 Euthanasia is the act of humanely killing animals for the Care and Use of Laboratory Animals (1), methods of euthanasia should be consistent with the AVMA

Arnold, Jonathan

293

Efficacy of Rodenticide Baits for the Control of Three Invasive Rodent Species in Hawaii  

Microsoft Academic Search

We tested the efficacy and palatability of nine commercial rodenticide bait formulations on Polynesian rats (Rattus exulans), roof rats (R. rattus), and house mice (Mus musculus). Efficacy varied by rodenticide tested and rodent species. Generally, rodenticides were more effective against mice than\\u000a for either of the rat species, and mice tended to consume more rodenticide bait than the laboratory chow

William C. PittLaura; Laura C. Driscoll; Robert T. Sugihara

2011-01-01

294

Detection of Toxoplasma gondii by PCR and Mouse Bioassay in Rodents of Ahvaz District, Southwestern Iran  

PubMed Central

Toxoplasma gondii is obligate coccidian zoonotic parasite. Felidae family is definitive and wide ranges of warm-blooded vertebrates are intermediate hosts for the parasite. Rodents are measured as an important source of T. gondii infection for the definitive host. Thus, this study aimed to investigate Toxoplasm infection in rodents of Ahvaz district, southwest of Iran. A total of 100 rodents (73 Rattus norvegicus, 21 Rattus rattus, and 6 Mus musculus) were collected and studied by GRA6PCR and mouse bioassay. The finding indicated that 6 out of 100 (6%) and 2 out of 100 (2%) samples were positive by PCR and mouse bioassay, respectively. The results show notable chronic infection in the rodent and potential transmission of the infection among animal and men in the region. Accordingly, this study recommended investigating of the T. gondii infection in definitive and other intermediate hosts in other points of Khuzestan province, Southwest, Iran. PMID:24605327

Saki, J.; Khademvatan, S.

2014-01-01

295

Rodent neurotoxicity bioassays for screening contaminated Great Lakes fish  

SciTech Connect

Standard laboratory rat neurotoxicity protocols were used to study the consequences resulting from the consumption of walleye (Stizostedion vitreum), whitefish (Coregonus clupeaformis), and lake trout (Salvelinus namaycush) from Lake Superior (LS) and the consumption of carp (Cyprinus carpio) from Little Lake Butte des Morte (LLBM) near Oshkosh, Wisconsin, USA. Two 90-d subchronic studies are described, including a 45-d exposure to fish diets using male Sprague-Dawley hooded rats, and a 90-d exposure to fish diets using female rats of the same species. Behavioral alterations were tested using a battery of behavioral tests. In addition, pharmacologic challenges using apomorphine and D-amphetamine were administered to the rats to reveal latent neurotoxic effects. Cumulative fish consumption data were recorded daily, weight gain recorded weekly, and behavior data collected prior to exposure, and on days 7, 14, 55 {+-} 2, 85 {+-} 2. Motor activity data were collected on days 30 {+-} 2, 60 {+-} 2, and 90 {+-} 2 of the feeding protocols. Brain tissue from rodents fed these fish were subsequently analyzed for either mercury (Hg) or polychlorinated biphenyls (PCB). Mercury concentrations were increased in the brains of the walleye-fed rats, and PCB concentrations ranged from 0.5 nl/L to 10 nl/L in the brains of rats fed carp from LLBM, a Lake Michigan tributary. Adult male rats fed LLBM carp for 45 d exhibited the greatest behavior responses to the dopaminergic agonist apomorphine on the accelerating rotarod, although these differences were not significant. The 90-d exposure of LS walleye or Hg-spiked LS walleye resulted in behavior alterations on tactile startle response and second footsplay. D-Amphetamine challenge caused changes in tactile startle response, second footsplay, and accelerating rotarod performance after consuming walleye diets. Rats fed LLBM carp had altered behavioral responses to apomorphine on the accelerating rotarod.

Beattie, M.K.; Hoffman, R. [Univ. of Minnesota, Duluth, MN (United States); Gerstenberger, S. [Univ. of Illinois, Urbana, IL (United States). Dept. of Veterinary Biosciences; Dellinger, J.A. [Medical Coll. of Wisconsin, Milwaukee, MI (United States). Dept. of Preventive Medicine

1996-03-01

296

Camera Trapping: A Contemporary Approach to Monitoring Invasive Rodents in High Conservation Priority Ecosystems  

PubMed Central

Invasive rodent species have established on 80% of the world's islands causing significant damage to island environments. Insular ecosystems support proportionally more biodiversity than comparative mainland areas, highlighting them as critical for global biodiversity conservation. Few techniques currently exist to adequately detect, with high confidence, species that are trap-adverse such as the black rat, Rattus rattus, in high conservation priority areas where multiple non-target species persist. This study investigates the effectiveness of camera trapping for monitoring invasive rodents in high conservation areas, and the influence of habitat features and density of colonial-nesting seabirds on rodent relative activity levels to provide insights into their potential impacts. A total of 276 camera sites were established and left in situ for 8 days. Identified species were recorded in discrete 15 min intervals, referred to as ‘events’. In total, 19 804 events were recorded. From these, 31 species were identified comprising 25 native species and six introduced. Two introduced rodent species were detected: the black rat (90% of sites), and house mouse Mus musculus (56% of sites). Rodent activity of both black rats and house mice were positively associated with the structural density of habitats. Density of seabird burrows was not strongly associated with relative activity levels of rodents, yet rodents were still present in these areas. Camera trapping enabled a large number of rodents to be detected with confidence in site-specific absences and high resolution to quantify relative activity levels. This method enables detection of multiple species simultaneously with low impact (for both target and non-target individuals); an ideal strategy for monitoring trap-adverse invasive rodents in high conservation areas. PMID:24599307

Rendall, Anthony R.; Sutherland, Duncan R.; Cooke, Raylene; White, John

2014-01-01

297

Reflective Cracking Study: First-level Report on Laboratory Shear Testing  

Microsoft Academic Search

This report contains a summary of the laboratory repeated load shear tests on mixes used as overlays on the Reflective Cracking Study Test Track at the Richmond Field Station. Evaluation of the results of the laboratory study on shear response of the overlay mixes reported herein included the effects of mix temperatures, air-void content, aging, mixing and compaction conditions, aggregate

Bor-Wen Tsai; David Jones; John T Harvey; Carl L. Monismith; I. Guada; J Signore

2008-01-01

298

Seven Principles of Instructional Content Design for a Remote Laboratory: A Case Study on ERRL  

ERIC Educational Resources Information Center

This paper discusses the results of a study of the requirements for developing a remote radio frequency (RF) laboratory for electrical engineering students. It investigates students' preferred usage of the technical content of a state-of-the-art RF laboratory. The results of this study are compared to previous findings, which dealt with other user…

Cagiltay, N. E.; Aydin, E.; Aydin, C. C.; Kara, A.; Alexandru, M.

2011-01-01

299

Laboratory and Observational Studies of Methyl Ethyl Ketone  

NASA Astrophysics Data System (ADS)

A large fraction of the detected interstellar molecules are complex organic molecules (COMs) containing five or more atoms. Despite the prominence of these species in many types of astrophysical environments, the formation processes for these molecules are not well-understood. We have therefore undertaken a combined laboratory, modeling, and observational program in an attempt to more fully understand the effects that physical environment have on the chemical composition of astronomical sources. As part of this effort, we have conducted deep submillimeter spectral line surveys of multiple interstellar sources with varying physical conditions including hot cores, shocked regions, low-mass star forming regions, and stellar outflows. These surveys were conducted using a broadband receiver at the Caltech Submillimeter Observatory (CSO), and are forerunner observations to our upcoming Herschel OT1 program to continue these surveys at higher frequencies. In order to fully analyze these spectral line surveys, we have also collected laboratory spectra of several suspected interstellar organic molecules. One such molecular target is methyl ethyl ketone (CH_3COCH_2CH_3, MEK), which is a likely candidate for interstellar detection. The spectra for MEK were collected from 8.7 to 18.3 GHz using the chirped-pulse waveguide Fourier Transform microwave (FTMW) spectrometer at New College Florida. We have also collected spectra of MEK in selected frequency ranges from 32 to 125 GHz using the direct absorption flow cell spectrometer at Emory University. We will report on the laboratory characterization of MEK and compare these results to our observational spectral line surveys.

Kroll, J. A.; Shipman, S.; Widicus Weaver, S. L.

2011-05-01

300

21 CFR 1250.96 - Rodent control.  

Code of Federal Regulations, 2012 CFR

...REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION INTERSTATE CONVEYANCE SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be maintained free of...

2012-04-01

301

21 CFR 1250.96 - Rodent control.  

Code of Federal Regulations, 2013 CFR

...REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION INTERSTATE CONVEYANCE SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be maintained free of...

2013-04-01

302

21 CFR 1250.96 - Rodent control.  

Code of Federal Regulations, 2010 CFR

...REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION INTERSTATE CONVEYANCE SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be maintained free of...

2010-04-01

303

21 CFR 1250.96 - Rodent control.  

Code of Federal Regulations, 2011 CFR

...REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION INTERSTATE CONVEYANCE SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be maintained free of...

2011-04-01

304

21 CFR 1250.96 - Rodent control.  

...REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION INTERSTATE CONVEYANCE SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be maintained free of...

2014-04-01

305

Factors influencing repeated seed movements by scatter-hoarding rodents in an alpine forest.  

PubMed

Scatter-hoarding rodents are effective dispersal agents for many plant species. Several studies have shown that rodents repeatedly re-cache seeds. The re-caching process often has a significant impact on final seedling establishment, but the factors determining its occurrence are poorly understood. In this study, we followed the fate of 3564 artificial seeds that varied in size, nutrient content and tannin content. Seeds cached closer to their original releasing plots were more likely to be re-cached, and to a further distance. Larger seeds were more likely to be re-cached than smaller ones, while nutrient and tannin content had little effect. Most plant species that depend on scatter-hoarding rodents for seed dispersal bear relatively large seeds, and large seeds are usually more likely to be dispersed and to establish seedlings, suggesting that the caching preferences of scatter-hoarding rodents may have played an important role in the evolution of large seeds. PMID:24759374

Wang, Bo; Chen, Jin; Corlett, Richard T

2014-01-01

306

Factors influencing repeated seed movements by scatter-hoarding rodents in an alpine forest  

PubMed Central

Scatter-hoarding rodents are effective dispersal agents for many plant species. Several studies have shown that rodents repeatedly re-cache seeds. The re-caching process often has a significant impact on final seedling establishment, but the factors determining its occurrence are poorly understood. In this study, we followed the fate of 3564 artificial seeds that varied in size, nutrient content and tannin content. Seeds cached closer to their original releasing plots were more likely to be re-cached, and to a further distance. Larger seeds were more likely to be re-cached than smaller ones, while nutrient and tannin content had little effect. Most plant species that depend on scatter-hoarding rodents for seed dispersal bear relatively large seeds, and large seeds are usually more likely to be dispersed and to establish seedlings, suggesting that the caching preferences of scatter-hoarding rodents may have played an important role in the evolution of large seeds. PMID:24759374

Wang, Bo; Chen, Jin; Corlett, Richard T.

2014-01-01

307

Analysis of protein pool of neuronal populations of cerebellar cortex in rodents of different species.  

PubMed

The protein pool of neuronal population of the cerebellar cortex was studied by interference cytometry in rodents occupying different ecological niches and differing by life style, nutrition habits, and motor activity. In all cell populations protein concentrations in the cytoplasm were higher than in the nucleus in all studied rodents and did not depend on the functional characteristics of neurons. The extreme values of protein content were determined for populations of granular and ganglion cells. High protein concentrations per volume unit of cell structure were detected in functionally different cerebellar neurons of gray rats, characterized by high motor activity and a certain degree of synanthropy, while low values were detected in mole rats, slow-moving underground rodents. Therefore, the specific protein pool of neuronal populations of the cerebellar cortex of rodents can be regarded as adaptation to habitation conditions. PMID:11276318

Orlyanskaya, T Y; Lyutikova, T M

2000-12-01

308

Preliminary data on the biodiversity of rodents and insectivores (Mammalia) in the periphery of Kisangani (D. R. Congo)  

Microsoft Academic Search

This study presents the species diversity of rodents and insectivores s.l. as observed in the forests around Kisangani (D.R. Congo) between 1979 and 2003. 7736 specimens were collected using Victor snap traps, Sherman live traps and pitfalls. In total, 49 small mammals species (36 rodents and 18 shrews) were identified of which 42 were actually captured and 7 more were

I. Mukinzi; P. G. B. Katuala; J. Kennis; M. Gambalemoke; N. Kadange; A. M. Dudu

2005-01-01

309

Experimental infections by Brucella suis type 4 in Alaskan rodents.  

PubMed

The susceptibility of nine species of rodents and one species of lagomorph to Brucella suis type 4 was studied experimentally. The rodent species included: guinea pig (Cavia porcellus), Scandinavian lemming (Lemmus lemmus), brown lemming (L. sibiricus), northern red-backed vole (Clethrionomys rutilis), varying lemmings (Dicrostonyx stevensoni and D. rubricatus), yellow-cheeked vole (Microtus xanthognathus), flying squirrel (Glaucomys sabrinus) and ground squirrel (Citellus parryii). The lagomorph, Lepus americanus (varying hare), was also studied. All of these species were readily infected by intraperitoneal inoculations of brucellae. Pathologic responses were not marked in most of these species. However, both species of varying lemmings responded dramatically to infections initiated by about as few as two cfu. All individuals of both species that were not killed eventually died from the infection. PMID:7463596

Miller, L G; Neiland, K A

1980-10-01

310

Rodents as potential couriers for bioterrorism agents.  

PubMed

Many pathogens that can cause major public health, economic, and social damage are relatively easily accessible and could be used as biological weapons. Wildlife is a natural reservoir for many potential bioterrorism agents, and, as history has shown, eliminating a pathogen that has dispersed among wild fauna can be extremely challenging. Since a number of wild rodent species live close to humans, rodents constitute a vector for pathogens to circulate among wildlife, domestic animals, and humans. This article reviews the possible consequences of a deliberate spread of rodentborne pathogens. It is relatively easy to infect wild rodents with certain pathogens or to release infected rodents, and the action would be difficult to trace. Rodents can also function as reservoirs for diseases that have been spread during a bioterrorism attack and cause recurring disease outbreaks. As rats and mice are common in both urban and rural settlements, deliberately released rodentborne infections have the capacity to spread very rapidly. The majority of pathogens that are listed as potential agents of bioterrorism by the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases exploit rodents as vectors or reservoirs. In addition to zoonotic diseases, deliberately released rodentborne epizootics can have serious economic consequences for society, for example, in the area of international trade restrictions. The ability to rapidly detect introduced diseases and effectively communicate with the public in crisis situations enables a quick response and is essential for successful and cost-effective disease control. PMID:23971813

Lõhmus, Mare; Janse, Ingmar; van de Goot, Frank; van Rotterdam, Bart J

2013-09-01

311

Laboratory Studies of Organic Compounds With Reflectance Spectroscopy  

NASA Astrophysics Data System (ADS)

In order to properly interpret reflectance spectra of any solar system surface from the earth to the Oort cloud, laboratory spectra of candidate materials for comparative analysis are needed. Although the common cosmochemical species (H2O, CO2, CO, NH3, and CH4) are well represented in the spectroscopic literature, comparatively little reflectance work has been done on organics from room to cryogenic temperatures at visible to near infrared wavelengths. Reflectance spectra not only enhance weak or unseen transmission features, they are also more analogous to spectra obtained by spacecraft that are imaging such bodies as giant planet moons, kuiper belt objects, centaurs, comets and asteroids, as well as remote sensing of the earth. The USGS Spectroscopy Laboratory is measuring reflectance spectra of organic compounds from room to cryogenic temperatures over the spectral range of 0.35 to 15.5 microns. This region encompasses the fundamental absorptions and many overtones and combinations of C, H, O, and N molecular bonds. Because most organic compounds belong to families whose members have similar structure and composition, individual species identification within a narrow wavelength range may be ambiguous. By measuring spectral reflectance of the pure laboratory samples from the visible through the near and mid-infrared, absorption bands unique to each can be observed, cataloged, and compared to planetary reflectance data. We present here spectra of organic compounds belonging to five families: the alkanes, alkenes, alkynes, aromatics, and cyanides. Common to all of these are the deep C-H stretch fundamental absorptions, which shift shortward from 3.35+ microns in alkanes to 3.25+ microns in aromatics, to 3.2+ microns in alkenes, and down to 3.0+ microns in alkynes. Mid-IR absorptions due to C-H bending deformations at 6.8+ and 7.2+ microns are also identified. In the near infrared these stretching and bending fundamentals yield a diagnostic set of combination absorptions at approximately 2.3 microns, as well as the first C-H stretching overtones at 1.6 to 1.7 microns, and even the second stretching overtones at 1.2+ microns. Additionally, the spectral properties of these organic materials have applications to remote sensing of terrestrial environments, including hazardous waste and disaster site characterization.

Curchin, J. M.; Clark, R. N.; Hoefen, T. M.

2007-12-01

312

Laboratory measurements in support of radar studies of Titan seas  

NASA Astrophysics Data System (ADS)

Data from Cassini RADAR instrument observations of Titan's lakes and seas show tantalizing hints that in some locations the radar signals might penetrate the liquids, returning measurable reflections from the solid surfaces beneath. At the microwave frequencies used by the RADAR instrument, non-polar liquid alkanes such as methane, ethane, and propane are fairly transparent, supporting the possibility that propagation through the liquids at Titan occurs. But relatively small amounts of other species dissolved in a liquid can strongly influence its microwave absorption coefficient. The dissolution of small amounts of sodium chloride in water, which increases the absorption coefficient by orders of magnitude, illustrates the potential of this effect. At Titan it is almost certain that some of the organic materials observed on the surface, and possibly other species, would dissolve in the methane-ethane mixture thought to constitute the bulk of the seas and lakes. If the microwave propagation constants of the liquids were known, Cassini RADAR data could provide estimates of depth profiles for areas yielding lake-bottom returns, and lower limits to depth for those areas where returns are absent. But the effects of anticipated dissolved species on the microwave properties of liquid alkane mixtures are largely unknown. Laboratory measurements could provide the key to inferring the lake-depth implications of Cassini RADAR results. There are multiple laboratory techniques available for measuring refractive indices and absorption coefficients of liquid samples at microwave frequencies. In the case of liquids relevant to Titan, the primary challenge is to maintain the samples and experimental apparatus at temperatures and pressures that keep the samples in the liquid phase, but this is not an impossible task. Other considerations include ensuring that the composition of a sample within the apparatus is well known. Notably, it is important that all surfaces in contact with the samples at any stage of the experiments do not affect the composition of the samples. An opportunity might arise to conduct such measurements as an extension of a task recently funded by the NASA Astrobiology Institute. That task calls for measuring the solubility of expected Titan materials, including but not limited to species found in tholins, in liquid methane-ethane mixtures. If such solutions are to be generated for that task, it would be prudent to use them for microwave experiments also. This presentation will describe candidate techniques for making these measurements and suggest possible applications to the Cassini data. This work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA.

Spilker, T. R.; Hodyss, R. P.; Beauchamp, P. M.; Reh, K. R.

2009-04-01

313

A SURVEY OF LABORATORY AND STATISTICAL ISSUES RELATED TO FARMWORKER EXPOSURE STUDIES  

EPA Science Inventory

Developing internally valid, and perhaps generalizable, farmworker exposure studies is a complex process that involves many statistical and laboratory considerations. Statistics are an integral component of each study beginning with the design stage and continuing to the final da...

314

Feasibility study of an orbiting laboratory for testing CSI technology  

NASA Technical Reports Server (NTRS)

A concept for an orbiting laboratory for testing Controls-Structures Integration (CSI) technology is described. The CSI-Star concept reflects a lower cost, higher risk approach. The concept supports demonstration and validation testing for critical CSI technologies at a cost of $20M to $26M with a 1-year reliability of approximately 0.9. The Ball Aerospace QuickStar bus is the carrier for the CSI test article. QuickStar is launched as a secondary payload on the McDonnell Douglas Delta 2. The QuickStar/Delta 2 approach is flight proven. The CSI test article is a 20 foot, 1 Hz, truss beam which is deployed from the QuickStar bus. The test article is well instrumented for quality system identification. The laboratory provides three layers of active control consisting of global vibration suppression along the truss beam, vibration isolation between the beam and instrument platforms, and vibration compensation through the use of gimbaled platforms which point lasers relative to optical sensor targets. The configuration simulates the dynamics of multi-instrument science platforms such as those of the Earth Observation System (EOS) while maintaining strong ties to astrophysics missions such as the Optical Interferometer. Uplink/downlink services and a reprogrammable computer provide flexibility for long-term investigations by members of the CSI community (NASA, DoD, academia, and industry). CSI-Star fills the gap between short-term experiments, which have been conducted primarily on the Shuttle, and future science missions which require the technology. The on-orbit maturity of CSI technology must be established to obtain acceptance by project managers and to promote injection of the technology into future science missions.

Bicos, Andrew S.; Loboda, Gregory G.

1993-01-01

315

Wide Distribution and Genetic Diversity of “Candidatus Neoehrlichia mikurensis” in Rodents from China  

PubMed Central

“Candidatus Neoehrlichia mikurensis” was detected by PCR in 4.0% (34/841) of the rodents tested in this study. The 34 rodents represented nine species from seven regions of China. Phylogenetic analyses based on the partial groEL and nearly entire 16S rRNA gene sequences of the agent revealed genetic diversity, which was correlated with its geographic origins. PMID:23183973

Li, Hao; Jiang, Jiafu; Tang, Fang; Sun, Yi; Li, Zengde; Zhang, Weilong; Gong, Zhengda; Liu, Kun; Yang, Hong

2013-01-01

316

Mating strategies of a nocturnal, desert rodent ( Dipodomys spectabilis )  

Microsoft Academic Search

Summary The mating system of a nocturnal, desert rodent, the banner-tailed kangaroo rat (Dipodomys spectabilis) was studied through direct observation, live-trapping, and radiotelemetry over a 13-month period from August 1986 to August 1987. Mating behavior varied from exclusive matings between male and female neighbors to competitive mate searching and direct male competition. In summer matings and early in a November

Jan A. Randall

1991-01-01

317

Beyond the rodent model: Calorie restriction in rhesus monkeys  

Microsoft Academic Search

Lifespan extension and reduction of age-related disease by calorie restriction (CR) are among the most consistent findings\\u000a in gerontological research. The well known effects of CR have been demonstrated many times in rodents and other short-lived\\u000a species. However, effects of CR on aging in longer-lived species, more closely related to humans, were unknown until recently.\\u000a Studies of CR and aging

Donald K. Ingram; George S. Roth

1997-01-01

318

PHYLOGENETICS OF THE NEW WORLD RODENT FAMILY HETEROMYIDAE  

Microsoft Academic Search

The family Heteromyidae includes 6 genera of rodents traditionally placed in 3 subfamilies endemic to the Nearctic and northern Neotropical biogeographic regions. Although several of these taxa represent intensively studied members of North and Central American ecosystems (e.g., kangaroo rats and pocket mice), phylogenetic relationships within and among subfamilies, genera, and species-groups are not well understood. Here, we used maximum-likelihood,

Lois F. Alexander; Brett R. Riddle

2005-01-01

319

The quantitative study of sexual and natural selection in the wild and in the laboratory  

Microsoft Academic Search

\\u000a I discuss the continuum of approaches that exist when studying sexual or natural selection in the wild and the laboratory.\\u000a These range from behavioural observations in the laboratory, via experimental manipulations of particular traits or environments,\\u000a to phenomenological studies in nature. I focus on the study of body size and related life history traits, particularly drawing\\u000a from our own studies

WOLF BLANCKENHORN

320

Propylene oxide: genotoxicity profile of a rodent nasal carcinogen.  

PubMed

Propylene oxide (PO) is a DNA-reactive genotoxic agent; that is, it reacts with DNA to produce lesions in the genetic material. PO also induces tumors in rodents, although only at high concentrations and at portals of entry. This review of PO's genotoxicity profile is organized according to endpoints measured, that is, nonmutational or mutational endpoints, and as to whether the results were from in vitro or in vivo studies. In addition to results of experimental studies, PO's genotoxicity for humans is assessed by reviewing results of published biomarker studies. The weight of evidence indicates that although it is genotoxic, PO's potency as a DNA-reactive mutagen is weak. Other aspects of PO's overall tissue toxicities are also reviewed, with attention to glutathione (GSH) depletion and its consequences, that is, cell proliferation, death, and necrosis. These toxic tissue responses occur in the same anatomical regions in rodents as do the PO-induced tumors. Furthermore, some of these tissue toxicities can produce effects that may either augment PO's DNA-reactive mutagenicity or be genotoxic in themselves, not dependent on PO's DNA reactivity. Although its DNA reactivity may be a necessary component of PO's overall genotoxicity and rodent carcinogenicity, it is likely not sufficient, and the associated tissue toxicities, which are rate-limiting, also seem to be required. This complex mode of action has implications for estimations of PO's cancer potential in humans, especially at low exposure concentrations. PMID:17661214

Albertini, Richard J; Sweeney, Lisa M

2007-01-01

321

Leishmania species: Detection and identification by nested PCR assay from skin samples of rodent reservoirs  

PubMed Central

Many rodent species act as reservoir hosts of zoonotic cutaneous leishmaniasis in endemic areas. In the present study a simple and reliable assay based on nested PCR was developed for the detection and identification of Leishmania parasites from rodent skin samples. We designed Leishmania-specific primers that successfully amplified ITS regions of Leishmania major, Leishmania gerbilli and Leishmania turanica using nested PCR. Out of 95 field collected Rhombomys opimus, 21 were positive by microscopic examination and 48 by nested PCR. The percentage of gerbils infected with L. major, L. gerbilli and L. turanica was 3.2%, 1.1% and 27.4%, respectively. In 15.8% of the rodents, we found mixed natural infections by L. major and L. turanica, 1.1% by L. major and L. gerbilli, and 2.1% by the three species. We concluded that this method is simple and reliable for detecting and identifying Leishmania species circulating in rodent populations. PMID:20566364

Akhavan, Amir Ahmad; Mirhendi, Hossein; Khamesipour, Ali; Alimohammadian, Mohammad Hossein; Rassi, Yavar; Bates, Paul; Kamhawi, Shaden; Valenzuela, Jesus G.; Arandian, Mohammad Hossein; Abdoli, Hamid; Jalali-zand, Niloufar; Jafari, Reza; Shareghi, Niloufar; Ghanei, Maryam; Yaghoobi-Ershadi, Mohammad Reza

2010-01-01

322

Prevalence and Diversity of Bartonella Species in Commensal Rodents and Ectoparasites from Nigeria, West Africa  

PubMed Central

Background Bartonellae are fastidious bacteria causing persistent bacteremia in humans and a wide variety of animals. In recent years there is an increasing interest in mammalian bartonelloses in general and in rodent bartonelloses in particular. To date, no studies investigating the presence of Bartonella spp. in rodents and ectoparasites from Nigeria were carried out. Methodology/Principal Findings The aim of the current study was to investigate the presence of Bartonella spp. in commensal rodents and their ectoparasites in Nigeria. We report, for the first time, the molecular detection of Bartonella in 26% (46/177) of commensal rodents (Rattus rattus, R. norvegicus and Cricetomys gambianus) and 28% (9/32) of ectoparasite pools (Xenopsylla cheopis, Haemolaelaps spp., Ctenophthalmus spp., Hemimerus talpoides, and Rhipicephalus sanguineus) from Nigeria. Sequence analysis of the citrate synthase gene (gltA) revealed diversity of Bartonella spp. and genotypes in Nigerian rodents and their ectoparasites. Bartonella spp. identical or closely related to Bartonella elizabethae, Bartonella tribocorum and Bartonella grahamii were detected. Conclusions/Significance High prevalence of infection with Bartonella spp. was detected in commensal rodents and ectoparasites from Nigeria. The Bartonella spp. identified were previously associated with human diseases highlighting their importance to public health. Further studies need to be conducted to determine whether the identified Bartonella species could be responsible for human cases of febrile illness in Nigeria. PMID:23738028

Kamani, Joshua; Morick, Danny; Mumcuoglu, Kosta Y.; Harrus, Shimon

2013-01-01

323

Rhythmic 24 h Variation of Core Body Temperature and Locomotor Activity in a Subterranean Rodent (Ctenomys aff. knighti), the Tuco-Tuco  

PubMed Central

The tuco-tuco Ctenomys aff. knighti is a subterranean rodent which inhabits a semi-arid area in Northwestern Argentina. Although they live in underground burrows where environmental cycles are attenuated, they display robust, 24 h locomotor activity rhythms that are synchronized by light/dark cycles, both in laboratory and field conditions. The underground environment also poses energetic challenges (e.g. high-energy demands of digging, hypoxia, high humidity, low food availability) that have motivated thermoregulation studies in several subterranean rodent species. By using chronobiological protocols, the present work aims to contribute towards these studies by exploring day-night variations of thermoregulatory functions in tuco-tucos, starting with body temperature and its temporal relationship to locomotor activity. Animals showed daily, 24 h body temperature rhythms that persisted even in constant darkness and temperature, synchronizing to a daily light/dark cycle, with highest values occurring during darkness hours. The range of oscillation of body temperature was slightly lower than those reported for similar-sized and dark-active rodents. Most rhythmic parameters, such as period and phase, did not change upon removal of the running wheel. Body temperature and locomotor activity rhythms were robustly associated in time. The former persisted even after removal of the acute effects of intense activity on body temperature by a statistical method. Finally, regression gradients between body temperature and activity were higher in the beginning of the night, suggesting day-night variation in thermal conductance and heat production. Consideration of these day-night variations in thermoregulatory processes is beneficial for further studies on thermoregulation and energetics of subterranean rodents. PMID:24454916

Tachinardi, Patricia; Bicudo, José Eduardo Wilken; Oda, Gisele Akemi; Valentinuzzi, Verónica Sandra

2014-01-01

324

The role of hair in swimming of laboratory mice: implications for behavioural studies in animals  

E-print Network

. Since various hair and skin abnormalities are not uncommon in genetically modified or drug of genetically modified laboratory mouse and rat strains with abnormal hair makes the swim tests importantThe role of hair in swimming of laboratory mice: implications for behavioural studies in animals

Kalueff, Allan V.

325

Laboratory studies of the interaction of ions with condensed gases: Planetary applications  

NASA Technical Reports Server (NTRS)

The work described is concerned with laboratory studies of the processes that produce the ejection of molecules from the surfaces of condensed gas solids, the change in the chemistry of the surface materials, and the relationship of these results to processes occurring in the solar system. Included is a discussion of the experimental techniques employed in making these laboratory measurements.

Boring, J. W.; Johnson, R. E.

1990-01-01

326

Tick parasites of rodents in Romania: host preferences, community structure and geographical distribution  

PubMed Central

Background Ticks are among the most important vectors of zoonotic diseases in temperate regions of Europe, with widespread distribution and high densities, posing an important medical risk. Most ticks feed on a variety of progressively larger hosts, with a large number of small mammal species typically harbouring primarily the immature stages. However, there are certain Ixodidae that characteristically attack micromammals also during their adult stage. Rodents are widespread hosts of ticks, important vectors and competent reservoirs of tick-borne pathogens. Micromammal-tick associations have been poorly studied in Romania, and our manuscript shows the results of a large scale study on tick infestation epidemiology in rodents from Romania. Methods Rodents were caught using snap-traps in a variety of habitats in Romania, between May 2010 and November 2011. Ticks were individually collected from these rodents and identified to species and development stage. Frequency, mean intensity, prevalence and its 95% confidence intervals were calculated using the EpiInfo 2000 software. A p value of <0.05 was considered statistically significant. Results We examined 423 rodents (12 species) collected from six counties in Romania for the presence of ticks. Each collected tick was identified to species level and the following epidemiological parameters were calculated: prevalence, mean intensity and mean abundance. The total number of ticks collected from rodents was 483, with eight species identified: Ixodes ricinus, I. redikorzevi, I. apronophorus, I. trianguliceps, I. laguri, Dermacentor marginatus, Rhipicephalus sanguineus and Haemaphysalis sulcata. The overall prevalence of tick infestation was 29.55%, with a mean intensity of 3.86 and a mean abundance of 1.14. Only two polyspecific infestations were found: I. ricinus + I. redikorzevi and I. ricinus + D. marginatus. Conclusions Our study showed a relatively high diversity of ticks parasitizing rodents in Romania. The most common tick in rodents was I. ricinus, followed by I. redikorzevi. Certain rodents seem to host a significantly higher number of tick species than others, the most important within this view being Apodemus flavicollis and Microtus arvalis. The same applies for the overall prevalence of tick parasitism, with some species more commonly infected (M. arvalis, A. uralensis, A. flavicollis and M. glareolus) than others. Two rodent species (Mus musculus, Rattus norvegicus) did not harbour ticks at all. Based on our results we may assert that rodents generally can act as good indicators for assessing the distribution of certain tick species. PMID:23171665

2012-01-01

327

Synchrotron and laboratory studies utilizing a new powder diffraction technique  

SciTech Connect

We have developed a new type of powder diffractometer that is much more efficient than existing methods. The diffractometer has the potential of both high count rates and very high resolution when used at a synchrotron source. The laboratory based instrument has an order of magnitude improvement in count rate over existing methods. The method uses a focusing diffracted beam monochromator in combination with a multichannel detector. The incident x-rays fall on a flat plate or capillary sample and are intercepted by a bent focusing monochromator which has the focus of the bend at the sample surface. The powder diffraction lines emerging from the bent crystal monochromator are detected by a linear or 2-dimensional detector. This allows us to eliminate the background from fluorescence or other scattering and to take data over a range of 3[degrees] to 4[degrees] instead of one angle at a time thereby providing a large improvement over conventional diffractometers. Results are presented for fluorapatite Fe[sub 2]O[sub 3], and a high-TC superconductor.

Knapp, G.S.; Beno, M.A.; Jennings, G.; Engbretson, M.; Ramanathan, M.

1992-10-01

328

Synchrotron and laboratory studies utilizing a new powder diffraction technique  

SciTech Connect

We have developed a new type of powder diffractometer that is much more efficient than existing methods. The diffractometer has the potential of both high count rates and very high resolution when used at a synchrotron source. The laboratory based instrument has an order of magnitude improvement in count rate over existing methods. The method uses a focusing diffracted beam monochromator in combination with a multichannel detector. The incident x-rays fall on a flat plate or capillary sample and are intercepted by a bent focusing monochromator which has the focus of the bend at the sample surface. The powder diffraction lines emerging from the bent crystal monochromator are detected by a linear or 2-dimensional detector. This allows us to eliminate the background from fluorescence or other scattering and to take data over a range of 3{degrees} to 4{degrees} instead of one angle at a time thereby providing a large improvement over conventional diffractometers. Results are presented for fluorapatite Fe{sub 2}O{sub 3}, and a high-TC superconductor.

Knapp, G.S.; Beno, M.A.; Jennings, G.; Engbretson, M.; Ramanathan, M.

1992-10-01

329

Laboratory studies of molecular growth in the Titan ionosphere.  

PubMed

Experimental simulations of the initial steps of the ion-molecule reactions occurring in the ionosphere of Titan were performed at the synchrotron source Elettra in Italy. The measurements consisted of irradiating gas mixtures with a monochromatic photon beam, from the methane ionization threshold at 12.6 eV, up to and beyond the molecular nitrogen dissociative ionization threshold at 24.3 eV. Three gas mixtures of increasing complexity were used: N(2)/CH(4) (0.96/0.04), N(2)/CH(4)/C(2)H(2) (0.96/0.04/0.001), and N(2)/CH(4)/C(2)H(2)/C(2)H(4) (0.96/0.04/0.001/0.001). The resulting ions were detected with a high-resolution (1 T) FT-ICR mass spectrometer as a function of time and VUV photon energy. In order to interpret the experimental results, a Titan ionospheric model was adapted to the laboratory conditions. This model had previously allowed the identification of the ions detected in the Titan upper atmosphere by the ion neutral mass spectrometer (INMS) onboard the Cassini spacecraft. Comparison between observed and modeled ion densities validates the kinetic model (reactions, rate constants, product branching ratios) for the primary steps of molecular growth. It also reveals differences that we attribute to an intense surface chemistry. This result implies that heterogeneous chemistry on aerosols might efficiently produce HCN and NH(3) in the Titan upper atmosphere. PMID:19769328

Thissen, Roland; Vuitton, Veronique; Lavvas, Panayotis; Lemaire, Joel; Dehon, Christophe; Dutuit, Odile; Smith, Mark A; Turchini, Stefano; Catone, Daniele; Yelle, Roger V; Pernot, Pascal; Somogyi, Arpad; Coreno, Marcello

2009-10-22

330

Distinct Leishmania Species Infecting Wild Caviomorph Rodents (Rodentia: Hystricognathi) from Brazil  

PubMed Central

Background Caviomorph rodents, some of the oldest Leishmania spp. hosts, are widely dispersed in Brazil. Despite both experimental and field studies having suggested that these rodents are potential reservoirs of Leishmania parasites, not more than 88 specimens were analyzed in the few studies of natural infection. Our hypothesis was that caviomorph rodents are inserted in the transmission cycles of Leishmania in different regions, more so than is currently recognized. Methodology We investigated the Leishmania infection in spleen fragments of 373 caviomorph rodents from 20 different species collected in five Brazilian biomes in a period of 13 years. PCR reactions targeting kDNA of Leishmania sp. were used to diagnose infection, while Leishmania species identification was performed by DNA sequencing of the amplified products obtained in the HSP70 (234) targeting. Serology by IFAT was performed on the available serum of these rodents. Principal findings In 13 caviomorph rodents, DNA sequencing analyses allowed the identification of 4 species of the subgenus L. (Viannia): L. shawi, L. guyanensis, L. naiffi, and L. braziliensis; and 1 species of the subgenus L. (Leishmania): L. infantum. These include the description of parasite species in areas not previously included in their known distribution: L. shawi in Thrichomys inermis from Northeastern Brazil and L. naiffi in T. fosteri from Western Brazil. From the four other positive rodents, two were positive for HSP70 (234) targeting but did not generate sequences that enabled the species identification, and another two were positive only in kDNA targeting. Conclusions/Significance The infection rate demonstrated by the serology (51.3%) points out that the natural Leishmania infection in caviomorph rodents is much higher than that observed in the molecular diagnosis (4.6%), highlighting that, in terms of the host species responsible for maintaining Leishmania species in the wild, our current knowledge represents only the “tip of the iceberg.” PMID:25503973

Cássia-Pires, Renata; Boité, Mariana C.; D'Andrea, Paulo S.; Herrera, Heitor M.; Cupolillo, Elisa; Jansen, Ana Maria; Roque, André Luiz R.

2014-01-01

331

Learning Style and Laboratory Preference: A Study of Middle School Technology Education Teachers in Virginia  

NSDL National Science Digital Library

Laboratory instruction has long been a cornerstone of technology education pedagogy. The French realized the potential for technical laboratory instruction within general education in 1865 (Bennett, 1926). By the 1880s, the United States also realized the benefits of the technical laboratory for general education (Anderson, 1926). Despite these early roots and the continued practice of utilizing laboratory instruction within technology education, there is little research to support this teaching method. McCrory (1987) noted that there were no studies on laboratories (excluding machine safety) or new technology education equipment during the period 1980-1986. Laboratory studies during the period 1987-1993 concentrated on curriculum and did not focus on new instructional methods and strategies (Zuga, 1994). The adoption of modular technology education has only heightened the need for research on laboratory instructional methods. Since the middle of the 1980s, modular technology education has grown considerably. Brusic and LaPorte (2000) found that almost half of the technology education teachers they surveyed in Virginia taught in some type of modular lab. Despite such emerging research, opinions concerning the merit of modular technology education, especially commercially created packages, dominate the field of technology education. To address these opinions, this study investigated whether the preference for a conventional or modular laboratory is influenced by the learning style of the teacher. Target Audience: Middle School Faculty/Administrators

Reed, Philip A.

332

Performance testing of radiobioassay laboratories: In vitro measurements, fecal study report  

SciTech Connect

This study evaluated nine radiobioassay laboratories; performances in analyzing fecal samples to determine the samples' levels of radioactivity. A total of 135 artificial fecal samples were sent to nine laboratories. Each laboratory received five samples spiked with 9. 58 pCi of /sup 239/Pu, five samples spiked with 1.13 pCi /sup 239/Pu, and five unspiked blank samples. Four of the laboratories returned data for all samples; four reported they were unable to complete the analyses; one analyzed six samples (three blanks and three of the lower activity samples). Results reported by the laboratories were analyzed by statistical methods specified in the draft standard for relative bias, relative precision, and minimum detectable activity (MDA). The calculated relative biases of all laboratories were well within the criteria of the standard (/minus/0.25 to +0.5). Biases for three laboratories were about 5% and the two others were within +-20%. Relative precision statistics for all participating laboratories were lower than the acceptance criteria of the standard (40%). Relative precision was less than 15% for one laboratory; for two others, it was less than 10%; and for the remaining two, it was less than 5% of the acceptance criteria. For the MDA criterion, four of the five laboratories passed. For all four of the passing laboratories, the entire 90% confidence interval was less than the specified acceptable minimum detectable amount (acceptable MDA) of 1 pCi. for the fifth laboratory, the MDA was 80% above the acceptable MDA specified in the draft standard. 16 refs., 3 figs., 3 tabs.

MacLellan, J.A.

1988-09-01

333

Mammalogy Laboratory 5 -Rodents I: Hystricognathi, Sciuridae, Aplodontidae  

E-print Network

: Erethizon dorsatum (Porcupine) #12;3 Family Myocastoridae (Nutria or Coypu) Diagnosis: Robust; pes much; nocturnal. Range: North, Central and South America Representative Genera: Erethizon, Coendu Material in Lab

Sullivan, Jack

334

Mammalogy Laboratory 6 -Rodents II: Castoridae, Geomyidae, Heteromyidae, Dipodidae, Muridae  

E-print Network

: Perognathus parvus (Great Basin pocket mouse) P. longimembris (Little pocket mouse) Chaetodipus penicillatus and Neotropical Genera: Heteromys, Liomys, Perognathus, Cheatodipus, Dipodomys, Microdipodops Material in Lab

Sullivan, Jack

335

Rodent-associated Bartonella in Saskatchewan, Canada.  

PubMed

Six species of wild rodents were sampled at 10 sites in 2002 and 2003 to determine the prevalence of Bartonella infections in rodent communities near Saskatoon, Saskatchewan, Canada. Isolates were characterized genotypically and compared with isolates found at other locations. Of 104 wild rodents examined, 57% were infected with Bartonella and prevalence within species varied from 49% for Richardson's ground squirrels (Spermophilus richardsonii) to 90% for Franklin's ground squirrels (S. franklinii). Infected rodents were found at all sites. Sequencing of a 379-bp portion of the citrate synthase gene was performed on 54 isolates and revealed 13 distinct genotypes, eight of which had not been described previously. The most common genotype detected in red-backed voles (Clethrionomys gapperi) was 99.1% similar to B. grahamii, a known human pathogen. Two of 10 Franklin's ground squirrels were concurrently infected with multiple Bartonella genotypes. All genotypes, with the exception of one detected in both Franklin's and thirteen-lined ground squirrels (S. tridecemlineatus), were found in only one host, and all genotypes from each species, with the exception of genotypes detected in red-backed voles, clustered together within the same relatedness group, suggesting that at least some Bartonella genotypes are specific to some rodent hosts. PMID:16417436

Jardine, Claire; Appleyard, Greg; Kosoy, Michael Y; McColl, Dorothy; Chirino-Trejo, Manuel; Wobeser, Gary; Leighton, Frederick A

2005-01-01

336

Rodent damage to natural and replanted mountain forest regeneration.  

PubMed

Impact of small rodents on mountain forest regeneration was studied in National Nature Reserve in the Beskydy Mountains (Czech Republic). A considerable amount of bark damage was found on young trees (20%) in spring after the peak abundance of field voles (Microtus agrestis) in combination with long winter with heavy snowfall. In contrast, little damage to young trees was noted under high densities of bank voles (Myodes glareolus) with a lower snow cover the following winter. The bark of deciduous trees was more attractive to voles (22% damaged) than conifers (8%). Young trees growing in open and grassy localities suffered more damage from voles than those under canopy of forest stands (?² = 44.04, P < 0.001). Natural regeneration in Nature Reserve was less damaged compared to planted trees (?² = 55.89, P < 0.001). The main factors influencing the impact of rodent species on tree regeneration were open, grassy habitat conditions, higher abundance of vole species, tree species preferences- and snow-cover condition. Under these conditions, the impact of rodents on forest regeneration can be predicted. Foresters should prefer natural regeneration to the artificial plantings. PMID:22666163

Heroldová, Marta; Bryja, Josef; Jánová, Eva; Suchomel, Josef; Homolka, Miloslav

2012-01-01

337

Rodent Damage to Natural and Replanted Mountain Forest Regeneration  

PubMed Central

Impact of small rodents on mountain forest regeneration was studied in National Nature Reserve in the Beskydy Mountains (Czech Republic). A considerable amount of bark damage was found on young trees (20%) in spring after the peak abundance of field voles (Microtus agrestis) in combination with long winter with heavy snowfall. In contrast, little damage to young trees was noted under high densities of bank voles (Myodes glareolus) with a lower snow cover the following winter. The bark of deciduous trees was more attractive to voles (22% damaged) than conifers (8%). Young trees growing in open and grassy localities suffered more damage from voles than those under canopy of forest stands (?2 = 44.04, P < 0.001). Natural regeneration in Nature Reserve was less damaged compared to planted trees (?2 = 55.89, P < 0.001). The main factors influencing the impact of rodent species on tree regeneration were open, grassy habitat conditions, higher abundance of vole species, tree species preferences- and snow-cover condition. Under these conditions, the impact of rodents on forest regeneration can be predicted. Foresters should prefer natural regeneration to the artificial plantings. PMID:22666163

Heroldová, Marta; Bryja, Josef; Jánová, Eva; Suchomel, Josef; Homolka, Miloslav

2012-01-01

338

ENVIRONMENTAL RADIOACTIVITY LABORATORY INTERCOMPARISON STUDIES PROGRAM: FISCAL YEAR 1980-1981  

EPA Science Inventory

The U.S. Environmental Protection Agency's intercomparison studies program for laboratories involved in environmental radiation measurements is described. The types of environmental samples distributed, the analyses required for each sample, the distribution schedule, and the sta...

339

CHARACTERIZATION AND LABORATORY SOIL TREATABILITY STUDIES FOR CREOSOTE AND PENTACHLOROPHENOL SLUDGES AND CONTAMINATED SOIL  

EPA Science Inventory

Information is presented from characterization and laboratory treatability phases of a 3-phase study pertaining to on-site treatability potential of soils containing hazardous constituents from wood-treatment waste. Specific information includes: (1) literature assessment of soil...

340

Laboratories for the 21st Century: Case Studies, Molecular Foundry, Berkeley, California  

SciTech Connect

This case study provides information on the Molecular Foundry, which incorporates Labs21 principles in its design and construction. The design includes many of the strategies researched at Lawrence Berkeley Laboratory for energy efficient cleanroom and data centers.

Not Available

2010-11-01

341

ENHANCED BIOREMEDIATION UTILIZING HYDROGEN PEROXIDE AS A SUPPLEMENTAL SOURCE OF OXYGEN: A LABORATORY AND FIELD STUDY  

EPA Science Inventory

Laboratory and field scale studies were conducted to investigate the feasibility of using hydrogen peroxide as a supplemental source of oxygen for bioremediation of an aviation gasoline fuel spill. Field samples of aviation gasoline contaminated aquifer material were artificially...

342

Studies of Photovoltaic Roofing Systems at Wind Engineering and Fluids Laboratory at Colorado State University  

E-print Network

Studies of Photovoltaic Roofing Systems at Wind Engineering and Fluids Laboratory at Colorado State of photovoltaic technology to generate electricity. Various innovative systems incorporating photovoltaic panels have been developed over the past decades. Prominent among them are photovoltaic roofing systems

343

NASA ER-2: Flying Laboratory for Earth Science Studies and Remote Sensing  

NASA Technical Reports Server (NTRS)

This viewgraph presentation shows views of the ER-2, NASA's Flying Laboratory for Earth Science Studies and Remote Sensing. The presentation briefly reviews the successes of the ER-2, and what the facility provides.

Navarro, Robert

2007-01-01

344

Earth Planets Space, 53, 539545, 2001 Study of local reconnection physics in a laboratory plasma  

E-print Network

Earth Planets Space, 53, 539­545, 2001 Study of local reconnection physics in a laboratory plasma University, New Jersey 08543, U.S.A. (Received June 20, 2000; Revised January 25, 2001; Accepted February 28

Ji, Hantao

345

FIELD AND LABORATORY OPERATIONS REPORT FOR THE OREGON WETLANDS STUDY  

EPA Science Inventory

The Oregon Wetlands Study (OWS) was designed to provide detailed characterizations of natural, created, and restored freshwater wetlands which is located in the urban environment of Portland, Oregon. his document discusses training the elementary, middle and high school teachers ...

346

Electric air filtration: theory, laboratory studies, hardware development, and field evaluations  

SciTech Connect

We summarize the results of a seven-year research project for the US Department of Energy (DOE) to develop electric air filters that extend the service life of high-efficiency particulate air (HEPA) filters used in the nuclear industry. This project was unique to Lawrence Livermore National Laboratory (LLNL), and it entailed comprehensive theory, laboratory studies, and hardware development. We present our work in three major areas: (1) theory of and instrumentation for filter test methods, (2) theoretical and laboratory studies of electric air filters, and (3) development and evaluation of eight experimental electric air filters.

Bergman, W.; Biermann, A.; Kuhl, W.; Lum, B.; Bogdanoff, A.; Hebard, H.; Hall, M.; Banks, D.; Mazumder, M.; Johnson, J.

1983-09-01

347

Navigating actions through the rodent parietal cortex  

PubMed Central

The posterior parietal cortex (PPC) participates in a manifold of cognitive functions, including visual attention, working memory, spatial processing, and movement planning. Given the vast interconnectivity of PPC with sensory and motor areas, it is not surprising that neuronal recordings show that PPC often encodes mixtures of spatial information as well as the movements required to reach a goal. Recent work sought to discern the relative strength of spatial vs. motor signaling in PPC by recording single unit activity in PPC of freely behaving rats during selective changes in either the spatial layout of the local environment or in the pattern of locomotor behaviors executed during navigational tasks. The results revealed unequivocally a predominant sensitivity of PPC neurons to locomotor action structure, with subsets of cells even encoding upcoming movements more than 1 s in advance. In light of these and other recent findings in the field, I propose that one of the key contributions of PPC to navigation is the synthesis of goal-directed behavioral sequences, and that the rodent PPC may serve as an apt system to investigate cellular mechanisms for spatial motor planning as traditionally studied in humans and monkeys. PMID:24860475

Whitlock, Jonathan R.

2014-01-01

348

Complete genome sequences of novel anelloviruses from laboratory rats.  

PubMed

Anelloviruses are nonenveloped single-stranded DNA viruses infecting a wide range of mammals. We report three complete genomes of novel anelloviruses detected in laboratory rats. Phylogenetic analysis demonstrates that these viruses are related to but distinct from recently described rodent Torque teno viruses (RoTTVs) found in wild rodent species. PMID:25657264

Nishiyama, Shoko; Dutia, Bernadette M; Sharp, Colin P

2015-01-01

349

Differential immune responses to Borrelia burgdorferi in European wild rodent species influence spirochete transmission to Ixodes ricinus L. (Acari: Ixodidae).  

PubMed Central

Immune responses to Borrelia burgdorferi and their influence on spirochete transmission to Ixodes ricinus were analyzed in the natural European reservoir hosts; i.e., the mouse species Apodemus flavicollis (yellow-necked mouse) and Apodemus sylvaticus (wood mouse) and the vole species Clethrionomys glareolus (bank vole), and, in addition, in the laboratory mouse strain NMRI. Naive and preimmunized rodents were infected either by artificially infected I. ricinus larvae or by intradermal injection of spirochetes. Independent of the species, all animals developed antibodies to various spirochetal antigens. However, antibodies to the outer surface proteins A (OspA) and B (OspB) were not found in recipients infected via ticks. Rodents of the genus Apodemus and of the NMRI strain showed higher levels of B. burgdorferi-specific antibodies than those of the species C. glareolus. The rate of spirochete transmission to noninfected ticks correlated with both the quality and quantity of spirochete-specific antibodies generated in the various species: high levels of spirochete-specific immunoglobulins correlated with low transmission rates. Furthermore, lower transmission rates were observed with rodents expressing antibodies to OspA and OspB (i.e., intradermally infected or immunized) than with those lacking these specificities (i.e., infected via ticks). The study provides evidence that transmission of B. burgdorferi from natural hosts to ticks is controlled by the specificity and quantity of spirochete-reactive antibodies and suggests that immunity to B. burgdorferi in natural reservoir hosts is an important regulatory factor in the horizontal transmission of B. burgdorferi in nature. Images PMID:7960113

Kurtenbach, K; Dizij, A; Seitz, H M; Margos, G; Moter, S E; Kramer, M D; Wallich, R; Schaible, U E; Simon, M M

1994-01-01

350

CHARGED DROPLET SCRUBBER FOR FINE PARTICLE CONTROL: LABORATORY STUDY  

EPA Science Inventory

The report gives results of a feasibility study of the application of charged droplet scrubbing for fine particle control. Results, using the TRW charged droplet scrubber, indicated that the method is feasible and applicable over a wide range of conditions. In the charged droplet...

351

Review of epidemiologic studies at Los Alamos National Laboratory  

SciTech Connect

Epidemiologic studies at Los Alamos are directed toward understanding potential health risks associated with activities pertaining to national energy and defense needs. Currently this research focuses on evaluating the effects of plutonium exposure in man. The major programs consist of (1) epidemiologic studies of the incidence of disease and mortality among plutonium and other workers at six Department of Energy (DOE) contractor facilities (Los Alamos, Rocky Flats, Mound, Savannah River, Hanford, and Oak Ridge), and (2) measurement of plutonium and other radionuclides in human tissues. Currently, investigations of mortality for Pantex workers and the surrounding general population are also being conducted for DOE in support of an Environment Impact Statement. This paper places emphasis on the activities of the national epidemiologic study of plutonium workers. The purpose of the plutonium workers study is to: (1) investigate whether adverse health effects are associated with exposures to plutonium, (2) explore whether adverse health effects are associated with exposure to transuranic elements, other radioisotopes, and hazardous substances that are found in nuclear facilities making routine use of plutonium, and (3) to describe in detail the nature of such health effects should they be discovered.

Voelz, G.L.; Wilkinson, G.S.; Acquavella, J.F.; Reyes, M.; McInroy, J.F.

1982-01-01

352

Coble NIST Mixture Interlaboratory NIST Inter-Laboratory Studies  

E-print Network

Institute of Standards and Technology. Certain commercial equipment, instruments, software and materials does it imply that any of the materials, instruments or equipment identified are necessarily the best.M. Butler, Forensic DNA Typing, p. 216) #12;Coble ­ NIST Mixture Interlaboratory Studies 02/20/2014 2 NIST

Perkins, Richard A.

353

An Innovative Method to Study Stokes' Law in the Laboratory  

ERIC Educational Resources Information Center

A new method is introduced to study the behaviour of the falling spherical ball in a viscous liquid using the well known Stokes' law. Experimental results are compared with those obtained by numerical calculations. Upper limits on the size and mass of the spherical balls of different materials used in the experiment are presented. (Contains 5…

Wadhwa, Ajay

2008-01-01

354

Modeling and testing of EVs — Preliminary study and laboratory development  

Microsoft Academic Search

Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid impact at different geographical areas, as well as driving and

Guang-Ya Yang; Francesco Marra; Arne Hejde Nielsen; Chresten Traholt

2011-01-01

355

A LABORATORY STUDY OF ARSENATE REDUCTION BY ORGANIC COMPOUNDS  

EPA Science Inventory

A variety of organic reductants will be explored. Initial studies will focus on molecules possessing alpha-hydroxy carboxylate and phenolate functional groups, organic groups commonly found in reducing environments. Mandelic acid was chosen as the alpha-hydroxy carboxylate sinc...

356

A prospective analysis of laboratory tests and imaging studies to detect hepatic lesions  

SciTech Connect

A prospective study of the ability of laboratory tests and liver imaging tests to detect hepatic metastases was performed. Eighty patients at risk for hepatic metastases but without clinical evidence of disease were tested with 13 laboratory tests and three liver imaging tests. No single laboratory test had greater than 65% accuracy in the detection of hepatic lesions. No combination of the laboratory tests increased this accuracy. If the laboratory tests were used with one of the liver imaging tests such as scintiscan, ultrasound, and computerized tomography, the accuracy was improved in some combinations to 76%. The CEA (carcinoembryonic antigen) assay when analyzed in patients with colorectal primaries had an accuracy of 79%. The results show that the laboratory tests alone are not sufficiently accurate to detect liver metastases. Additional accuracy can be obtained by the combined use of a single liver imaging test and selected laboratory tests. Use of all the liver imaging tests and laboratory tests lowers the accuracy and increases the expense and thus is unnecessary.

Kemeny, M.M. (National Inst. of Health, Bethesda, MD); Sugarbaker, P.H.; Smith, T.J.; Edwards, B.K.; Shawker, T.; Vermess, M.; Jones, A.E.

1982-02-01

357

Past and Future Work on Radiobiology Mega Studies: A Case Study at Argonne National Laboratory  

PubMed Central

Between 1952 and 1992 more than 200 large radiobiology studies were conducted in research institutes throughout Europe, North America and Japan to determine the effects of external irradiation and internal emitters on the life span and tissue toxicity development in animals. At Argonne National Laboratory, 22 external beam studies were conducted on nearly 700 beagle dogs and 50,000 mice between 1969 and 1992. These studies helped to characterize the effects of neutron and gamma irradiation on lifespan, tumorigenesis, and mutagenesis across a range of doses and dosing patterns. The records and tissues collected at Argonne during that time period have been carefully preserved and redisseminated. Using these archived data ongoing statistical work has been done and continues to characterize quality of radiation, dose, dose rate, tissue, and gender specific differences in the radiation responses of exposed animals. The ongoing application of newly developed molecular biology techniques to the archived tissues has revealed gene specific mutation rates following exposure to ionizing irradiation. The original and ongoing work with this tissue archive is presented here as a case study of a more general trend in the radiobiology mega studies. These experiments helped form the modern understanding of radiation responses in animals, and continue to inform development of new radiation models. Recent archival efforts have facilitated open access to the data and materials produced by these studies and so a unique opportunity exists to expand this continued research. PMID:22004930

Haley, Benjamin; Wang, Qiong; Wanzer, Beau; Vogt, Stefan; Finney, Lydia; Yang, Ping Liu; Paunesku, Tatjana; Woloschak, Gayle

2013-01-01

358

Dissociated vertical deviation-a clinical and laboratory study.  

PubMed Central

The previously reported nomenclature and clinical characteristics of dissociated vertical deviation have been recorded. The incidence and characteristics of DVD have been determined by evaluation of 1,000 consecutive strabismus or nystagmus patients, and with selected chart study carried out on the 111 DVD patients found in this series. Electro-oculographic studies of selected patients with DVD provided objective evidence of the speed and amplitude of the ocular movements in DVD. Bell phenomenon, strabismus sursoadductorius and the Bielschowsky phenomenon were recorded and compared to clinical findings of strabismus patients with DVD. The technique for the results of surgery for DVD were described. Dissociated vertical deviation was characterized as a component of the overall strabismus picture. Images FIGURE 1 A FIGURE 1 B FIGURE 1 C FIGURE 1 D FIGURE 1 E FIGURE 2 A FIGURE 2 B FIGURE 2 C FIGURE 3 A FIGURE 3 B FIGURE 3 C FIGURE 4 A FIGURE 4 B PMID:7020216

Helveston, E M

1980-01-01

359

Multimodality Rodent Imaging Chambers for Use Under Barrier Conditions With Gas Anesthesia  

PubMed Central

Purpose The ability to reproducibly and repeatedly image rodents in non-invasive imaging systems, such as small animal PET and CT, requires a reliable method for anesthetizing, positioning, and heating animals in a simple reproducible manner. In this paper we demonstrate that mice and rats can be reproducibly and repeatedly imaged using an imaging chamber designed to be rigidly mounted on multiple imaging systems. Procedures Mouse and rat imaging chambers were made of acrylic plastic and aluminum. MicroCT scans were used to evaluate the positioning reproducibility of the chambers in multi-modality and longitudinal imaging studies. The ability of the chambers to maintain mouse and rat body temperatures while anesthetized with gas anesthesia was also evaluated. Results Both the mouse and rat imaging chambers were able to reproducibly position the animals in the imaging systems with a small degree of error. Placement of the mouse in the mouse imaging chamber resulted in a mean distance of 0.23 mm per reference point in multimodality studies, whereas for longitudinal studies the mean difference was 1.11 mm. The rat chamber resulted in a mean difference of 0.46 mm in multimodality studies, and a mean difference of 4.31 mm in longitudinal studies per reference point. The chambers maintained rodent body temperatures at the set point temperature of 38°C. Conclusions The rodent imaging chambers were able to reproducibly position rodents in tomographs with a small degree of variability, and were compatible with routine use. The embedded anesthetic line and heating system was capable of maintaining the rodent’s temperature and anesthetic state, thereby enhancing rodent health and improving data collection reliability. PMID:18679755

Suckow, Chris; Kuntner, Claudia; Chow, Patrick; Silverman, Robert; Chatziioannou, Arion; Stout, David

2009-01-01

360

Salinity tolerance of Gyrodactylus salaris (Platyhelminthes, Monogenea): laboratory studies  

Microsoft Academic Search

The salinity tolerance of the freshwater monogenean Gyrodactylus salaris, infecting Atlantic salmon (Salmo salar) parr, was studied experimentally. Following direct transfer of infected fish from fresh water to 5.0‰ salinity, parasite population growth increased at the same rate as in fresh water and was positively correlated with temperature (1.4, 6.0, and 12.0°C). In 7.5‰ salinity the populations declined and became

Arnulf Soleng; Tor A. Bakke

1997-01-01

361

Laboratory Study of Hall Reconnection in Partially Ionized Plasmas  

SciTech Connect

The effects of partial ionization (ni/nn ? 1%) on magnetic reconnection in the Hall regime have been studied systematically in the Magnetic Reconnection Experiment (MRX). It is shown that, when neutrals are added the Hall quadrupole field pattern and thus electron flow is unchanged while the ion outflow speed is reduced due to ion-neutral drag. However, in constrast to theoretical predictions, the ion diffusion layer width does not change appreciably. Therefore, the total ion outflow flux and the normalized reconnection rate are reduced.

Eric E. Lawrence, Hanto Ji, Masaaki Yamaada and Jongsoo Yoo

2012-05-15

362

Experimental Study of Driven Magnetic Relaxation in a Laboratory Plasma  

NASA Astrophysics Data System (ADS)

The physics goal of the Driven Relaxation Experiment (DRX) is to form and sustain simply-connected driven-relaxed plasmas above the first Jensen-Chu linear resonance of the force-free equation (where the first resonance is the ``flipped'' Rosenbluth- Bussac spheromak). As shown recently by Tang & Boozer (PRL, 2005), the linear resonances are regularized in partially relaxed systems, thus removing the energy barriers which have been thought to constrain relaxed states to exist only below the first resonance. DRX will apply an ``over-driven'' boundary condition at the coaxial gun source, with ?gun 30 m-1 3?1. The DRX power system (10 kV, 125 kJ) will form and sustain the ˜10 eV plasma for about 0.5 ms, which is about 10 Sweet-Parker reconnection times and sufficient for the plasma to reach a driven-relaxed steady-state. We will measure the 2D structure of the equilibrium magnetic field and compare it with the first several linear eigenmodes of the force-free equation, and subsequently study the k-spectrum of the magnetic energy as well as the dynamics of relaxation. Other topics we will study include magnetic flux amplification and the role of boundary elongation on equilibrium/stability. Better understanding of these issues could lead to new ideas for confinement configurations. This poster will provide an overview of DRX and first experimental data. Supported by the LANL LDRD Program.

Hsu, S.; Madziwa-Nussinov, T.; Sirajuddin, D.; Light, M.

2007-11-01

363

Laboratory Studies in UV and EUV Solar Physics  

NASA Technical Reports Server (NTRS)

The Ion Beam Experiment at the Center for Astrophysics is dedicated to the study of ion-electron collision processes of importance in solar physics. The analysis of measurements of Electron Impact Excitation (EIE) from the 3s3p(exp 3)P(exp o) metastable state to the 3s3p(exp 1)P state of Si(2+) was completed during the past year and a paper describing the results is available as a preprint. Our current program is directed at measuring absolute cross sections for dielectronic recombination (DR) and EIE in Si(3+), one of the primary ions used for probing the solar transition region. Our study of DR is particularly concerned with the effects of electric and magnetic fields on the recombination rates. Measurements of silicon ions with charge greater than n=2 have necessitated upgrading the experiment with a new ion source. The new source is also suitable for producing C(2+) beams to be used for measurements of EIE and DR for that system. The source is expected to be capable of producing beams of more highly charged systems as well.

Parkinson, W. H.; Wagner, William J. (Technical Monitor)

2002-01-01

364

Past and Future Work on Radiobiology Mega-Studies: A Case Study At Argonne National Laboratory  

SciTech Connect

Between 1952 and 1992, more than 200 large radiobiology studies were conducted in research institutes throughout Europe, North America, and Japan to determine the effects of external irradiation and internal emitters on the lifespan and tissue toxicity development in animals. At Argonne National Laboratory, 22 external beam studies were conducted on nearly 700 beagle dogs and 50,000 mice between 1969 and 1992. These studies helped to characterize the effects of neutron and gamma irradiation on lifespan, tumorigenesis, and mutagenesis across a range of doses and dosing patterns. The records and tissues collected at Argonne during that time period have been carefully preserved and redisseminated. Using these archived data, ongoing statistical work has been done and continues to characterize quality of radiation, dose, dose rate, tissue, and gender-specific differences in the radiation responses of exposed animals. The ongoing application of newly-developed molecular biology techniques to the archived tissues has revealed gene-specific mutation rates following exposure to ionizing irradiation. The original and ongoing work with this tissue archive is presented here as a case study of a more general trend in the radiobiology megastudies. These experiments helped form the modern understanding of radiation responses in animals and continue to inform development of new radiation models. Recent archival efforts have facilitated open access to the data and materials produced by these studies, and so a unique opportunity exists to expand this continued research.

Haley, Benjamin; Wang, Qiong; Wanzer, Beau; Vogt, Stefan; Finney, Lydia; Yang, Ping Liu; Paunesku, Tatjana; Woloschak, Gayle

2011-09-06

365

Subsite Awareness in Neuropathology Evaluation of National Toxicology Program (NTP) Studies: A Review of Select Neuroanatomical Structures with their Functional Significance in Rodents  

PubMed Central

This review manuscript is designed to serve as an introductory guide in neuroanatomy for toxicologic pathologists evaluating general toxicity studies. The manuscript provides an overview of approximately 50 neuroanatomical subsites and their functional significance across seven coronal sections of the brain. Also reviewed are three sections of the spinal cord, cranial and peripheral nerves (trigeminal and sciatic respectively), and intestinal autonomic ganglia. The review is limited to the evaluation of hematoxylin and eosin (H&E) stained tissue sections, as light microscopic evaluation of these sections is an integral part of the first-tier toxicity screening of environmental chemicals, drugs, and other agents. Prominent neuroanatomical sites associated with major neurological disorders are noted. This guide, when used in conjunction with detailed neuroanatomic atlases may aid in an understanding of the significance of functional neuroanatomy, thereby improving the characterization of neurotoxicity in general toxicity and safety evaluation studies. PMID:24135464

Rao, Deepa B.; Little, Peter B.; Sills, Robert

2013-01-01

366

A comparative study of several agents alone and combined in protection of the rodent kidney from warm ischaemia: Methylprednisolone, propranolol, furosemide, mannitol, and adenosine triphosphate-magnesium chloride  

Microsoft Academic Search

The effect of 60 min of in situ warm ischaemia (37°C) on renal function was investigated in the rat model. In addition, the effect of pretreatment with intravenously administered furosemide, mannitol, propranolol, methylprednisolone, and adenosine triphosphate-magnesium chloride (ATP-MgCl2), singly or in combination, was studied. The ischaemic kidney was effectively protected by the administration of methylprednisolone alone but not by furosemide,

G. Aydin; S. E. Okiye; H. Zincke

1983-01-01

367

Helicobacter acinonychis: Genetic and Rodent Infection Studies of a Helicobacter pylori-Like Gastric Pathogen of Cheetahs and Other Big Cats  

PubMed Central

Insights into bacterium-host interactions and genome evolution can emerge from comparisons among related species. Here we studied Helicobacter acinonychis (formerly H. acinonyx), a species closely related to the human gastric pathogen Helicobacter pylori. Two groups of strains were identified by randomly amplified polymorphic DNA fingerprinting and gene sequencing: one group from six cheetahs in a U.S. zoo and two lions in a European circus, and the other group from a tiger and a lion-tiger hybrid in the same circus. PCR and DNA sequencing showed that each strain lacked the cag pathogenicity island and contained a degenerate vacuolating cytotoxin (vacA) gene. Analyses of nine other genes (glmM, recA, hp519, glr, cysS, ppa, flaB, flaA, and atpA) revealed a ?2% base substitution difference, on average, between the two H. acinonychis groups and a ?8% difference between these genes and their homologs in H. pylori reference strains such as 26695. H. acinonychis derivatives that could chronically infect mice were selected and were found to be capable of persistent mixed infection with certain H. pylori strains. Several variants, due variously to recombination or new mutation, were found after 2 months of mixed infection. H. acinonychis ' modest genetic distance from H. pylori, its ability to infect mice, and its ability to coexist and recombine with certain H. pylori strains in vivo should be useful in studies of Helicobacter infection and virulence mechanisms and studies of genome evolution. PMID:14702304

Dailidiene, Daiva; Dailide, Giedrius; Ogura, Keiji; Zhang, Maojun; Mukhopadhyay, Asish K.; Eaton, Kathryn A.; Cattoli, Giovanni; Kusters, Johannes G.; Berg, Douglas E.

2004-01-01

368

Chronic cyanide exposure: a clinical, radioisotope, and laboratory study.  

PubMed Central

The effect of chronic cyanide exposure in the electroplating sections of three factories employing 36 workers was studied and compared with a control group. The concentration of cyanides to which the workers were exposed was measured. The regression line showing the relationship between thiocyanates in urine and the concentration of cyanides in the air was plotted. Increased percentages of haemoglobin and lymphocyte count were present in all exposed workers, in addition to punctate basophilia in 28 workers. Cyanmethaemoglobin was found to be characteristic. Apart from other complaints, two men with psychosis similar to one case reported in therapeutic thiocyanate intoxication were found. Twenty of the workers had thyroid enlargements to a variable degree and consistency, in two of whom it resembled lymphadenoid goitre. Thyroid 131I uptakes at 4 and 24 hours were significantly higher than in the controls, while 131PBI was unchanged. The reason for this iodine deficiency-like action is discussed. PMID:1156569

El Ghawabi, S H; Gaafar, M A; El-Saharti, A A; Ahmed, S H; Malash, K K; Fares, R

1975-01-01

369

KETENE FORMATION IN INTERSTELLAR ICES: A LABORATORY STUDY  

SciTech Connect

The formation of ketene (H{sub 2}CCO, ethenone) in polar and apolar ices was studied with in situ 0.8 MeV proton irradiation, far-UV photolysis, and infrared spectroscopic analyses at 10-20 K. Using isotopically enriched reagents, unequivocal evidence was obtained for ketene synthesis in H{sub 2}O-rich and CO{sub 2}-rich ices, and several reaction products were identified. Results from scavenging experiments suggested that ketene was formed by free-radical pathways, as opposed to acid-base processes or redox reactions. Finally, we use our results to draw conclusions about the formation and stability of ketene in the interstellar medium.

Hudson, Reggie L.; Loeffler, Mark J., E-mail: Reggie.Hudson@NASA.gov [Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2013-08-20

370

Laboratory Studies of Heterogeneous Chemical Processes of Atmospheric Importance  

NASA Technical Reports Server (NTRS)

The objective of this study is to conduct measurements of chemical kinetics parameters for heterogeneous reactions of importance in the stratosphere and the troposphere. It involves the elucidation of the mechanism of the interaction of HC1 vapor with ice surfaces, which is the first step in the heterogeneous chlorine activation processes, as well as the investigation of the atmospheric oxidation mechanism of soot particles emitted by biomass and fossil fuels. The techniques being employed include turbulent flow- chemical ionization mass spectrometry and optical ellipsometry, among others. The next section summarizes our research activities during the first year of the project, and the section that follows consists of the statement of work for the second year.

Molina, Mario J.

2003-01-01

371

Urine radiobioassay intercomparison results from the Intercomparison Studies Program at Oak Ridge National Laboratory  

Microsoft Academic Search

The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix\\u000a human urine quality-assurance\\/quality-control (QA\\/QC) samples to radiobioassay analysis laboratories. Samples are provided\\u000a to these laboratories as “single-blind” or “double-blind” unknowns, spiked with radioactive-solution standards at “low” levels\\u000a (e.g., 0–250 mBq·kg?1 for alpha-emitters). Participants use the results as a tool for self-evaluation and

Norman Bores; Michael K Schultz; J. M. Rankin; A. J. Denton; G. F. Payne

2008-01-01

372

7 CFR 58.247 - Insect and rodent control program.  

Code of Federal Regulations, 2010 CFR

... false Insect and rodent control program. 58.247 Section 58.247 Agriculture Regulations of the Department of Agriculture...Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In...

2010-01-01

373

Detection of Cryptosporidium and Giardia in clinical laboratories in Europe--a comparative study.  

PubMed

To determine the routine diagnostic methods used and compare the performance in detection of oocysts of Cryptosporidium species and cysts of Giardia intestinalis in faecal samples by European specialist parasitology laboratories and European clinical laboratories. Two sets of seven formalin-preserved faecal samples, one containing cysts of Giardia intestinalis and the other, containing oocysts of Cryptosporidium, were sent to 18 laboratories. Participants were asked to examine the specimens using their routine protocol for detecting these parasites and state the method(s) used. Eighteen laboratories answered the questionnaire. For detection of Giardia, 16 of them used sedimentation/concentration followed by light microscopy. Using this technique the lower limit of detection of Giardia was 17.2 cysts/mL of faeces in the best performing laboratories. Only three of 16 laboratories used fluorescent-conjugated antibody-based microscopy. For detection of Cryptosporidium acid-fast staining was used by 14 of the 17 laboratories that examined the samples. With this technique the lower limit of detection was 976 oocysts/mL of faeces. Fluorescent-conjugated antibody-based microscopy was used by only five of the 17 laboratories. There was variation in the lower limit of detection of cysts of Giardia and oocysts of Cryptosporidium between laboratories using the same basic microscopic methods. Fluorescent-conjugated antibody-based microscopy was not superior to light microscopy under the conditions of this study. There is a need for a larger-scale multi-site comparison of the methods used for the diagnosis of these parasites and the development of a Europe-wide laboratory protocol based upon its findings. PMID:24033667

Manser, M; Granlund, M; Edwards, H; Saez, A; Petersen, E; Evengard, B; Chiodini, P

2014-01-01

374

Laboratory studies of electrochemical treatment of industrial azo dye effluent.  

PubMed

Removal of color and reduction of chemical oxygen demand (COD) in an industrial azo dye effluent containing chiefly reactive dyes were investigated under single-pass conditions at a dimensionally stable anode (DSA) in a thin electrochemical flow reactor at different current densities, flow rates, and dilutions. With 50% diluted effluent, decolorization was achieved up to 85-99% at 10-40 mA/ cm2 at 5 mL/min flow rate and 50-88% at 30-40 mA/ cm2 at high (10-15 mL/min) flow rates. The COD reduction was maximum (81%) at 39.9 mA/cm2 or above when solution-electrode contact time (Ct) was as high as 21.7 s/cm2 and decreased as Ct declined at a given current density. Cyclic voltammetric studies suggesting an indirect oxidation of dye molecules over the anode surface were carried out at a glassy carbon electrode. The effect of pH on decolorization and COD reduction was determined. An electrochemical mechanism mediated by OCl- operating in the decolorization and COD reduction processes was suggested. The effluent was further treated with NaOCI. The oxidized products from the treated effluents were isolated and confirmed to be free from chlorine-substituted products by IR spectroscopy. From the apparent pseudo-first-order rate data, the second-order rate coefficients were evaluated to be 2.9 M(-1) s(-1) at 5 mL/ min, 76.2 M(-1) s(-1) at 10 mL/min, and 156.1 M(-1) s(-1) at 15 mL/ min for color removal, and 1.19 M(-1) s(-1) at 5 mL/min, 1.79 M(-1) s(-1) at 10 mL/min, and 3.57 M(-1) s(-1) at 15 mL/min for COD reduction. Field studies were also carried out with a pilot-scale cell at the source of effluent generation of different plants corresponding to the industry. Decolorization was achieved to about 94-99% with azo dye effluents at 0.7-1.0 L/min flow costing around Indian Rupees 0.02-0.04 per liter, and to about 54-75% in other related effluents at 0.3-1.0 L/min flow under single-pass conditions. PMID:15884385

Vaghela, Sanjay S; Jethva, Ashok D; Mehta, Bhavesh B; Dave, Sunil P; Adimurthy, Subbarayappa; Ramachandraiah, Gadde

2005-04-15

375

Laboratory Studies in UV and EUV Solar Physics  

NASA Technical Reports Server (NTRS)

The Ion Beam Experiment at the Center for Astrophysics is dedicated to the study of ion-electron collision processes of importance in solar physics. A paper describing our most recent measurement 'Absolute cross section for Si(2+)(3s3p(sup 3)Rho (sup 0) yields 3s3p(sup 1)Rho(sup 0)) electron-impact excitation' was published during the past year. Dr. Paul Janzen received his PhD. from the Harvard Physics Department on the basis of this and other work, such as the new electron cyclotron resonance (ECR) ion source. The ion source is producing stable beams with large currents for our present work on C(2+), and it also produces stable beams with large currents of more highly charged systems, for future work on systems such as O(4+). The past year has been focussed on our current program to measure absolute cross sections for Electron Impact Excitation (EIE) in C(2+), one of the primary ions used for probing the solar transition region. C(2+) beams produced by the ion source have been transported to the interaction region of the experiment, where the collisions are studied, and Visiting Scientist Dr. Adrian Daw is currently collecting data to measure the C(2+)(2s2p(sup 3)Rho(sup 0) yields 2p(sup 2)(sup 3)Rho) EIE cross section as a function of collision energy, under the guidance of Drs. John Kohl, Larry Gardner and Bill Parkinson. Also this year, modifications were made to the ECR ion source in order to produce greater currents of highly charged ions. Testing of the ion source was completed. Modifications were designed to extend the photon detection capabilities of the apparatus to shorter UV wavelengths, or EUV. Following the work on C(2+)(2s2p(sup 3)Pho(sup 0) yields 2p(sup 2)(sup 3)Rho), the extended UV detection capabilities will be used to measure the C(2+)(2s(sup 2)(sup 1)S yields 2s2p(sup 1)Rho(sup 0)) EIE cross section. The EUV modifications complement those of the new ion source, by enabling detection of EUV light generated by high charge state ions and putting us in a position to measure the excitation cross sections for more highly charged ions as well.

Parkinson, William

2003-01-01

376

A study of divergent TA teaching styles in inquiry-based laboratory education  

NASA Astrophysics Data System (ADS)

This dissertation is a study of the divergent behaviors evidenced by different TAs teaching inquiry based physics laboratories with minimal preparation on how to use techniques such as Socratic dialogue, wait time, and time management. The revised physics laboratory curricula, a four semester laboratory sequence, were studied over the course of two years and one of the laboratory manuals was rewritten and new techniques of TA training developed in order to align TA behavior with the ideals of inquiry based education. This revision was only partially successful, aiding TAs dramatically in improving their time management skills and use of their time, however not yielding dramatic improvements in their use of Socratic dialogue or leading questions.

Little, James H.

377

a Laboratory Study of Single Sulfate Aerosols Using Electrodynamic Suspension  

NASA Astrophysics Data System (ADS)

Bithermal isopiestic measurements of the water vapor pressure of the (NH(,4))(,2)SO(,4)-NH(,4)HSO(,4) -H(,2)O system at room temperature have been made using single nanogram particles electrodynamically suspended in a modified quadrupole trap. Particle composition changed from NH(,4)HSO(,4) to (NH(,4))(,2)SO(,4) as NH(,3) gas was absorbed in situ. Particle relative mass during solid liquid phase transformations was measured with an electroslatic balance. Constant water activity curves for both dilute and supersaturated solutions are displayed on a (NH(,4))(,2)SO(,4) -NH(,4)HSO(,4)-H(,2)O phase diagram. From these measurements, a model is presented to explain the dynamics of dissolving mixed crystals. Applying electrolyte solution thermodynamics, values of the activity coefficient for aqueous solutions of (NH(,4))(,2)SO(,4) and NH(,4)HSO(,4) are calculated. The measured water activity of the various ammonium-hydrogen-sulfate solutions is compared to the predicted value of two models. The free energy of formation for the three crystalline structures of (NH(,4))(,2)SO(,4), (NH(,4))(,3)H(SO(,4))(,2) and NH(,4)HSO(,4) is approximated using the Gibbs-Duhem relation and our measured values of saturated solutions. Using nucleation theory and the measured composition and water activity of the solution upon crystallization, the specific nucleation barrier is deduced. Speculation about the size of the critical nucleus as a function of composition is made assuming that the total nucleation barrier is constant. A discussion of the study's application to atmospheric processes is included.

Spann, James Frederick, Jr.

378

Emissions of tar-containing binders: a laboratory study.  

PubMed

In Switzerland, hot recycling of tar-containing pavements is a subject of much dispute between environmentalists, road authorities and constructors. The main reason for this controversy comes from a lack of knowledge about the amount of hazardous compounds emitted, especially polycyclic aromatic hydrocarbons (PAHs), and the resulting health risk for road workers. On this background we decided to initiate a research project to study the emission behaviour of tar-containing materials. Mixtures of tar and bitumen with variable PAH content were heated in an open reactor flask at different temperatures to identify and quantify the key parameters of PAH emissions. The expected linear correlation between PAH concentration in the fumes and in the binder was found only for binder mixtures with PAH concentrations above 5000 ppm. This was traced back to the problem that a change of the PAH content in the binder was always accompanied by a change of other parameters, like viscosity. In the experiments with temperature variation, emissions of individual PAHs correlated well with vapor pressure. However, for Naphthalene and, in a lesser degree, for 3-ring PAHs too, a partial depletion of these compounds in the vapour was observed in some experiments. The effect is a slower increase with temperature for these compounds compared to 4-6-ring PAHs. This is one reason why the commonly used set of EPA-PAHs, which includes naphthalene and 3-ring PAHs, is considered inappropriate for the assessment of the health hazard in the case of tar-containing materials in hot recycling. PMID:17365290

Hugener, Martin; Emmenegger, Lukas; Mattrel, Peter

2007-02-15

379

Safety studies on intrahepatic or intratumoral injection of oncolytic vesicular stomatitis virus expressing interferon-beta in rodents and nonhuman primates.  

PubMed

Toxicology studies were performed in rats and rhesus macaques to establish a safe starting dose for intratumoral injection of an oncolytic vesicular stomatitis virus expressing human interferon-beta (VSV-hIFNbeta) in patients with hepatocellular carcinoma (HCC). No adverse events were observed after administration of 7.59 x 10(9) TCID(50) (50% tissue culture infective dose) of VSV-hIFNbeta into the left lateral hepatic lobe of Harlan Sprague Dawley rats. Plasma alanine aminotransferase and alkaline phosphatase levels increased and platelet counts decreased in the virus-treated animals on days 1 and 2 but returned to pretreatment levels by day 4. VSV-hIFNbeta was also injected into normal livers or an intrahepatic McA-RH7777 HCC xenograft established in Buffalo rats. Buffalo rats were more sensitive to neurotoxic effects of VSV; the no observable adverse event level (NOAEL) of VSV-hIFNbeta in Buffalo rats was 10(7) TCID(50). Higher doses were associated with fatal neurotoxicity and infectious virus was recovered from tumor and brain. Compared with VSV-hIFNbeta, toxicity of VSV-rIFNbeta (recombinant VSV expressing rat IFN-beta) was greatly diminished in Buffalo rats (NOAEL, >10(10) TCID(50)). Two groups of two adult male rhesus macaques received 10(9) or 10(10) TCID(50) of VSV-hIFNbeta injected directly into the left hepatic lobe under computed tomographic guidance. No neurological signs were observed at any time point. No abnormalities (hematology, clinical chemistry, body weights, behavior) were seen and all macaques developed neutralizing anti-VSV antibodies. Plasma interleukin-6, tumor necrosis factor-alpha, and hIFN-beta remained below detection levels by ELISA. On the basis of these studies, we will be proposing a cautious approach to dose escalation in a phase I clinical trial among patients with HCC. PMID:19911974

Jenks, Nathan; Myers, Rae; Greiner, Suzanne M; Thompson, Jill; Mader, Emily K; Greenslade, Andrew; Griesmann, Guy E; Federspiel, Mark J; Rakela, Jorge; Borad, Mitesh J; Vile, Richard G; Barber, Glen N; Meier, Thomas R; Blanco, Michael C; Carlson, Stephanie K; Russell, Stephen J; Peng, Kah-Whye

2010-04-01

380

7 CFR 58.247 - Insect and rodent control program.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Insect and rodent control program. 58.247...and Operating Procedures § 58.247 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program as...

2011-01-01

381

7 CFR 58.247 - Insect and rodent control program.  

...2014-01-01 2014-01-01 false Insect and rodent control program. 58.247...and Operating Procedures § 58.247 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program as...

2014-01-01

382

7 CFR 58.147 - Insect and rodent control program.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Insect and rodent control program. 58.147...and Operating Procedures § 58.147 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program....

2012-01-01

383

7 CFR 58.147 - Insect and rodent control program.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Insect and rodent control program. 58.147...and Operating Procedures § 58.147 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program....

2010-01-01

384

7 CFR 58.147 - Insect and rodent control program.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Insect and rodent control program. 58.147...and Operating Procedures § 58.147 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program....

2011-01-01

385

7 CFR 58.247 - Insect and rodent control program.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Insect and rodent control program. 58.247...and Operating Procedures § 58.247 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program as...

2012-01-01

386

7 CFR 58.247 - Insect and rodent control program.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Insect and rodent control program. 58.247...and Operating Procedures § 58.247 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program as...

2013-01-01

387

7 CFR 58.147 - Insect and rodent control program.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Insect and rodent control program. 58.147...and Operating Procedures § 58.147 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program....

2013-01-01

388

7 CFR 58.147 - Insect and rodent control program.  

...2014-01-01 2014-01-01 false Insect and rodent control program. 58.147...and Operating Procedures § 58.147 Insect and rodent control program. In addition...the performance of a regularly scheduled insect and rodent control program....

2014-01-01

389

Northwestern University New Researcher Checklist: Evanston Campus Rodent Users  

E-print Network

and Access to CCM Facilities Register for Facility Orientation and Hands-On Rodent Euthanasia o Contact the CCM Training Office to register for Facility Orientation and Hands-On Rodent Euthanasia training: 312-503-2758 o Facility Orientation and Hands-On Rodent Euthanasia are: Held on Tuesdays at 10:30am and Fridays

Contractor, Anis

390

Integration of Pig-a, micronucleus, chromosome aberration, and Comet assay endpoints in a 28-day rodent toxicity study with 4-nitroquinoline-1-oxide.  

PubMed

As part of the Stage III Pig-a multilaboratory validation trial, we examined the induction of CD59-negative reticulocytes and total red blood cells (RET(CD59-) and RBC(CD59-) , respectively) in male Sprague Dawley(®) rats treated with 4-nitroquinoline-1-oxide (4NQO), for 28 consecutive days by oral gavage, at doses of 1.25, 2.50, 3.75, 5.00, and 7.50 mg kg(-1) day(-1) (the high dose group was sacrificed on Day 15 due to excessive morbidity/mortality). Animals also were evaluated for: micronucleated reticulocytes (mnRET) by flow cytometry; DNA damage in peripheral blood, liver, and stomach using the Comet assay; and chromosome aberrations (CAb) in peripheral blood lymphocytes (PBL). All endpoints were analyzed at two or more timepoints where possible. Mortality, body and organ weights, food consumption, and clinical pathology also were evaluated, and demonstrated that the maximum tolerated dose was achieved at 5.00 mg kg(-1) day(-1) . The largest increases observed for the genetic toxicology endpoints (fold-increase compared to control, where significant; all at 5.00 mg kg(-1) day(-1) on Day 29) were: RET(CD59-) (21X), RBC(CD59-) (9.0X), and mnRET (2.0X). In contrast, no significant increases were observed for the CAb or Comet response, in any tissue analyzed, at any timepoint. Because 4NQO is a well known mutagen, clastogen, and carcinogen, the lack of response for these latter endpoints was unexpected. These results emphasize the extreme care that must betaken in dose and endpoint selection when incorporating genotoxicity endpoints into routine toxicity studies as has been recommended or is under consideration by various regulatory and industrial bodies. PMID:22020836

Stankowski, Leon F; Roberts, Daniel J; Chen, Hepei; Lawlor, Timothy; McKeon, Marie; Murli, Hemalatha; Thakur, Ajit; Xu, Yong

2011-12-01

391

MRI-monitored transcatheter intraarterial delivery of SPIO-labeled natural killer cells to hepatocellular carcinoma: preclinical studies in a rodent model  

PubMed Central

Object To test the hypotheses that intraarterial (IA) infusion allows for targeted natural killer (NK) lymphocyte delivery to hepatocellular carcinoma (HCC) and that iron oxide labeling allows for quantitative visualization of IA NK delivery with magnetic resonance imaging (MRI). Materials and Methods Experiments received institutional animal care and use committee approval. NK-92MI cells were labeled with superparamagnetic iron oxide (SPIO) nanoparticles. Cell viability, labeling efficacy, and cell phantom imaging studies were performed. Six rats were each implanted with two HCC tumors. Catheter was placed in proper hepatic artery for NK infusion. MRI T2* measurements for tumor and normal liver were compared pre and post infusion and correlated with histological measurements; Prussian blue staining was used for labeled NK identification. Spearman correlation coefficients and t-tests were calculated for statistical analyses. Results Increasing SPIO incubation concentration decreased cell viability. Labeling efficacy was 88.0±3.1% (mean±SD) across samples. The spatial extent of T2*-weighted contrast and R2* relaxivity values increased for cell phantom samples incubated with increasing SPIO concentrations. T2* measurements decreased in the tumor and normal liver tissues after NK infusion (p<0.001); ?T2* was greater in tumors than in normal liver tissue (p<0.001). Histological measurements demonstrated increased NK delivery to the tumor compared to the normal liver (p<0.001). ?T2* was well-correlated with histological NK measurements (?=0.70). Conclusion IA infusion permitted selective delivery of NK cells to HCC. Transcatheter delivery of SPIO-labeled NK cells can be quantitatively visualized with MRI. PMID:23249649

Sheu, Alexander Y.; Zhang, Zhuoli; Omary, Reed A.; Larson, Andrew C.

2013-01-01

392

Effect of laser (? 660 nm) and LED (? 630 nm) photobiomodulation on formocresol-induced oral ulcers: a clinical and histological study on rodents.  

PubMed

The aim of this study was to evaluate, clinically and histologically, the influence of laser and LED photobiomodulation in the healing of formocresol-induced oral mucosa ulcers of rats. We used 60 Wistar rats in which oral ulcers were induced on the gingiva of the lower incisors. Forty-eight hours after inducing the ulcers, the animals were divided into three groups: laser, LED, and untreated. Animals from the laser group received irradiation with GaAlAs, 660 nm, CW, 40 mW, ? 4 mm(2), 4.8 J/cm(2). Animals from the LED group received irradiation with InGaAIP, 630 nm, 150 mW, 4.8 J/cm(2), 0.8 cm spot. Forty-eight hours after oral ulcer induction, both irradiations were applied in a punctuate manner in the center of the ulcer at 48-h interval until the end of the experimental period. The animals were killed at 3, 5, 7, and 11 days after day 0. The results of the clinical evaluation showed that the laser and LED phototherapies were able to accelerate the healing of formocresol-induced oral ulcers, which occurred first in the laser group (ANOVA, p?

de Carvalho, Fabiola Bastos; Andrade, Aline Silva; Rasquin, Luis Cardoso; de Castro, Isabele Vieira; Cangussu, Maria Cristina Teixeira; Pinheiro, Antônio Luiz Barbosa; Dos Santos, Jean Nunes

2015-01-01

393

NEOSPORA CANINUM DETECTED IN WILD RODENTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The role of rodents in the epidemiology of neosporosis was investigated by assaying brain tissue of wild mice and rats for Neospora caninum. Both mouse and rat brain tissue were extracted for total DNA, and subjected to two different N. caninum-specific nested PCR assays. A portion of brain tissue...

394

Embargoed African Rodents and Monkeypox Virus  

MedlinePLUS

... distribution, transport, or release into the environment, of prairie dogs and six specific genera of African rodents. The joint order was enacted as part of the public health response to the first reported outbreak of monkeypox in the United States. On November 4, 2003, ...

395

Object Recognition Memory and the Rodent Hippocampus  

ERIC Educational Resources Information Center

In rodents, the novel object recognition task (NOR) has become a benchmark task for assessing recognition memory. Yet, despite its widespread use, a consensus has not developed about which brain structures are important for task performance. We assessed both the anterograde and retrograde effects of hippocampal lesions on performance in the NOR…

Broadbent, Nicola J.; Gaskin, Stephane; Squire, Larry R.; Clark, Robert E.

2010-01-01

396

Too many rodent carcinogens: Mitogenesis increases mutagenesis  

Microsoft Academic Search

A clarification of the mechanism of carcinogenesis is developing at a rapid rate. This new understanding undermines many assumptions of current regulatory policy toward rodent carcinogens and necessitates rethinking the utility and meaning of routine animal cancer tests. At a recent watershed meeting on carcinogenesis, much evidence was presented suggesting that mitogenesis plays a dominant role in carcinogenesis. Our own

B. N. Ames; L. S. Gold

1990-01-01

397

Climate, Deer, Rodents, and Acorns as Determinants  

E-print Network

Climate, Deer, Rodents, and Acorns as Determinants of Variation in Lyme-Disease Risk Richard S the determinants of Lyme-disease risk (density and Borrelia burgdorferi-infection prevalence of nymphal Ixodes Lyme disease (Dutchess County, New York). We used a model comparison approach to simultaneously test

398

A protocol for a lung neovascularization model in rodents  

PubMed Central

By providing insight into the cellular events of vascular injury and repair, experimental model systems seek to promote timely therapeutic strategies for human disease. The goal of many current studies of neovascularization is to identify cells critical to the process and their role in vascular channel assembly. We propose here a protocol to analyze, in an in vivo rodent model, vessel and capillary remodeling (reorganization and growth) in the injured lung. Sequential analyses of stages in the assembly of vascular structures, and of relevant cell types, provide further opportunities to study the molecular and cellular determinants of lung neovascularization. PMID:18323809

Jones, Rosemary C; Capen, Diane E; Petersen, Bodil; Jain, Rakesh K; Duda, Dan G

2009-01-01

399

Nonhuman gamblers: lessons from rodents, primates, and robots  

PubMed Central

The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offers valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics), to make the case for a greater degree of methodological integration in future studies on pathological gambling. PMID:24574984

Paglieri, Fabio; Addessi, Elsa; De Petrillo, Francesca; Laviola, Giovanni; Mirolli, Marco; Parisi, Domenico; Petrosino, Giancarlo; Ventricelli, Marialba; Zoratto, Francesca; Adriani, Walter

2014-01-01

400

Evidence from studies in rodents and in isolated adipocytes that agonists of the chemerin receptor CMKLR1 may be beneficial in the treatment of type 2 diabetes  

PubMed Central

The literature is unclear on whether the adipokine chemerin has pro- or anti-inflammatory properties or plays any role in the aetiology of type 2 diabetes or obesity. To address these questions, and in particular the potential of agonists or antagonists of the chemerin receptor CMKLR1 in the treatment of type 2 diabetes and obesity, we studied the metabolic phenotypes of both male and female, CMKLR1 knockout and heterozygote mice. We also investigated changes in plasma chemerin levels and chemerin gene mRNA content in adipose tissue in models of obesity and diabetes, and in response to fasting or administration of the insulin sensitizing drug rosiglitazone, which also has anti-inflammatory properties. The effects of murine chemerin and specific C-terminal peptides on glucose uptake in wild-type and CMKLR1 knockout adipocytes were investigated as a possible mechanism by which chemerin affects the blood glucose concentration. Both male and female CMKLR1 knockout and heterozygote mice displayed a mild tendency to obesity and impaired glucose homeostasis, but only when they were fed on a high-fat died, rather than a standard low-fat diet. Obesity and impaired glucose homeostasis did not occur concurrently, suggesting that obesity was not the sole cause of impaired glucose homeostasis. Picomolar concentrations of chemerin and its C15- and C19-terminal peptides stimulated glucose uptake in the presence of insulin by rat and mouse wild-type epididymal adipocytes, but not by murine CMKLR1 knockout adipocytes. The insulin concentration-response curve was shifted to the left in the presence of 40 pM chemerin or its C-15 terminal peptide. The plasma chemerin level was raised in diet-induced obesity and ob/ob but not db/db mice, and was reduced by fasting and, in ob/ob mice, by treatment with rosiglitazone. These findings suggest that an agonist of CMKLR1 is more likely than an antagonist to be of value in the treatment of type 2 diabetes and to have associated anti-obesity and anti-inflammatory activities. One mechanism by which an agonist of CMKLR1 might improve glucose homeostasis is by increasing insulin-stimulated glucose uptake by adipocytes.

Wargent, Edward T.; Zaibi, Mohamed S.; O’Dowd, Jacqueline F.; Cawthorne, Michael A.; Wang, Steven J.; Stocker, Claire J.

2015-01-01

401

Wellness Center use at Los Alamos National Laboratory: a descriptive study  

SciTech Connect

This study describes employee participation during the first six months of the Los Alamos National Laboratory's corporate Wellness Program. We describe temporal patterns of use, preferred activities, frequency of use, and characteristics of employees participating in Wellness activities. Characteristics of Wellness participants are compared with characteristics of the Laboratory population. During this period the Wellness Center, a multi-use facility that houses Wellness Program activities, had 17,352 visits. Employees visiting the Wellness Center were typical of the Laboratory population in their racial and ethnic characteristics, but different in their sex and age composition. Wellness participants were younger and more likely to be female than the Laboratory population. 6 refs., 19 tabs.

Wiggs, L.D.; Wilkinson, G.S.; Weber, C.

1985-10-01

402

Seismic hazard studies for the High Flux Beam Reactor at Brookhaven National Laboratory  

SciTech Connect

This paper presents the results of a calculation to determine the site specific seismic hazard appropriate for the deep soil site at Brookhaven National Laboratory (BNL) which is to be used in the risk assessment studies being conducted for the High Flux Beam Reactor (HFBR). The calculations use as input the seismic hazard defined for the bedrock outcrop by a study conducted at Lawrence Livermore National Laboratory (LLNL). Variability in site soil properties were included in the calculations to obtain the seismic hazard at the ground surface and compare these results with those using the generic amplification factors from the LLNL study. 9 refs., 8 figs.

Costantino, C.J.; Heymsfield, E. (City Coll., New York, NY (United States). Dept. of Civil Engineering); Park, Y.J.; Hofmayer, C.H. (Brookhaven National Lab., Upton, NY (United States))

1991-01-01

403

Investigating Neural Correlates of Behavior in Freely Behaving Rodents Using Inertial Sensors  

PubMed Central

Simultaneous behavior and multielectrode neural recordings in freely behaving rodents holds great promise to study the neural bases of behavior and disease models in combination with genetic manipulations. Here, we introduce the use of three-axis accelerometers to characterize the behavior of rats and mice during chronic neural recordings. These sensors were small and light enough to be worn by rodents and were used to record three-axis acceleration during freely moving behavior. A two-layer neural network-based pattern recognition algorithm was developed to extract the natural behavior of mice from the acceleration data. Successful recognition of resting, eating, grooming, and rearing are shown using this approach. The inertial sensors were combined with continuous 24-h recordings of neural data from the striatum of mice to characterize variations in neural activity with circadian cycles and to study the neural correlates of spontaneous action initiation. Finally, accelerometers were used to study the performance of rodents in traditional operant conditioning, where they were used to extract the reaction time of rodents. Thus the addition of accelerometer recordings of rodents to chronic multielectrode neural recordings provides great value for a number of neuroscience applications. PMID:20427622

Venkatraman, Subramaniam; Jin, Xin; Costa, Rui M.

2010-01-01

404

EFFECTS OF FOOD AVAILABILITY ON SURVIVAL, GROWTH, AND REPRODUCTION OF THE GRASS SHRIMP PALAEMONETES PUGIO: A LABORATORY STUDY  

EPA Science Inventory

Grass shrimp are abundant, ecologically important inhabitants of estuarine ecosystems; adults and embryos have been used extensively in laboratory experiments, including studies of the impacts of environmental toxicants. However, optimal laboratory feeding conditions for grass sh...

405

Partial Rodent Genetic Models for Bipolar Disorder  

PubMed Central

Bipolar disorder (BPD) is a complex clinical phenomenon. This episodic illness comprises at least four features/components: depression, mania, vulnerability to mood swings in euthymic BPD patients, and spontaneous cyclicity in at least some BPD patients. Currently, there is no rodent genetic model capable of encompassing the whole phenotype of BPD exists; however, recent genetic-behavioral studies have delineated partial models for some components of BPD, namely, depression, mania, and vulnerability or resilience to mood swings. p11 knockout (KO), vesicular monoamine transporter 2 (VMAT2) heterozygous KO, and neural cell adhesion molecule (NCAM) KO mice display anhedonia-like symptoms, and treatment with antidepressants rescues this anhedonia-related phenotype. Mutant CLOCK, glutamate receptor 6 (GluR6) KO, and extracellular signal-regulated kinase 1 (ERK1) KO mice exhibit mania-like behavioral clusters referred to as excessive behavioral excitement; at least some of the exhibited behaviors can be rescued through treatment with mood stabilizers or atypical antipsychotics. Neuronal glucocorticoid receptor (GR) overexpressing, B-cell lymphoma 2 (Bcl-2) heterozygous KO, and Bcl-2-associated athanogene (BAG1) heterozygous KO mice show vulnerability to mood swings. In contrast, neuronal BAG1 overexpressing mice display resilience to mood swings. These mutant mouse strains and the behavioral approaches used to characterize these strains offer an emerging set of research tools for the comprehensive understanding of various components of BPD, and the interrelation of these components at the molecular, cellular, and neuronal circuitry levels. These partial genetic models can also be used as complementary tools to augment other existing behavioral tests and paradigms in drug development for BPD. PMID:25236551

Chen, Guang; Henter, Ioline D.; Manji, Husseini K.

2015-01-01

406

Moss species benefits from breakdown of cyclic rodent dynamics in boreal forests.  

PubMed

Bryophytes have increased in abundance in northern regions, and climate changes have been proposed to account for this change. However, changes in the population dynamics of microtine rodents may also contribute to changes in bryophyte abundance. New evidence indicates a tendency for microtine rodent population oscillations to change from periodicity of 3-5 years to become irregular or acyclic. The impact on ecosystem functioning is potentially great. We study the impact of variation in microtine rodent population characteristics, such as cycle length and amplitude, on the population dynamics of the boreal, clonal moss Hylocomium splendens. We use experimental and observational demographic data to construct 127 scenarios representing all combinations of disturbance type (gap formation and/or clipping), period (cyclic with 4, 6, 12, or 24 years between rodent peaks; or acyclic with constant or stochastically varying annual disturbance severity) and disturbance severity (fraction of individuals affected by disturbance in each year relative to the maximum disturbance carried out in the field experiment; seven levels). Population data collected in the field during 13 years were used as a baseline scenario. By subjecting all scenarios to stochastic matrix modeling, we demonstrate considerable impact of microtine rodent on the population dynamics of H. splendens, most notably when rodent populations fluctuate with short periods and high peak disturbance severities. Under the same average disturbance severity, H. splendens population growth rates are highest in acyclic scenarios and are progressively reduced with increasing peak disturbance severities (i.e., with increasing period). Stochastic elasticity analyses show that in less variable environments mature segment survival contributes more to the population growth rate, while in more variable environments the regeneration pathway (branching of older parts of the plant) plays a stronger role, inevitably leading to lower population fitness. Our results support the hypothesis that breakdown of cyclic rodent population dynamics accentuates increase in the abundance of H. splendens and other large bryophytes in boreal forests in Norway, observed empirically in recent years and primarily ascribed to climatic change. PMID:17918409

Rydgren, Knut; Økland, Rune H; Picó, F Xavier; de Kroon, Hans

2007-09-01

407

Coordinated International Laboratory Studies of Meteorites Supporting Rosetta Mission's Asteroid Flybys  

Microsoft Academic Search

The Rosetta spacecraft flew by asteroid 2867 Steins in September 2008, collecting images, UV, visible and IR spectra and radar reflections. A flyby of the ˜95 km diameter asteroid 21 Lutetia is scheduled for July, 2010. Laboratory studies using meteoritic and terrestrial samples are designed to support interpretation of the observations of the asteroid targets. The goal is to study

L. A. McFadden; M. F. A'Hearn; E. Ammanito; E. Cloutis; A. Coradini; M. de Sanctis; L. M. Feaga; M. Fulchignoni; E. Hadamcik; T. Hiroi; L. Kolokolova; A. Levasseur-Regourd; A. A. Ovcharenko; W. J. Parker; V. A. Psarev; J. Renard

2009-01-01

408

Laboratory Instructions and Study Guide for Human Anatomy. Part Two, Fourth Edition.  

ERIC Educational Resources Information Center

During the process of studying the specific course content of human anatomy, students are being educated to expand their vocabulary, learn to deal successfully with complex tasks, and use a specific way of thinking. This is the second volume in a set of laboratory instructions and study notes which are designed to accompany a lecture series in…

Conrey, Kathleen

409

A Laboratory Study of Wilmington Tar Zone CO2 Injection Project  

Microsoft Academic Search

The authors conducted a laboratory study of heavy-oil recovery by COâ injection to support the Wilmington, CA tar zone COâ injection project operated by Long Beach Oil Development Co. The study comprised (1) phase behavior of Wilmington tar zone reservoir oil and COâ, and (2) phase behavior of the oil and the refinery gas used for the field project, (3)

Vega Sankur; J. L. Creek; S. S. DiJulio; A. S. Emanuel

1986-01-01

410

Course of Study; Altus Linguistic Laboratory Altus Independent School District 18, Altus, Oklahoma, 1968.  

ERIC Educational Resources Information Center

A course of study in the teaching of English to Spanish-speaking migrant children at elementary level was developed and put into use during the 1967-68 school year by the Altus Public Schools Migrant Linguistic Laboratory in Oklahoma. This course of study was designed to include an oral English emphasis, without destroying pride in the mother…

Oklahoma State Dept. of Education, Oklahoma City.

411

LABORATORY STUDIES ON THE STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL  

EPA Science Inventory

The stability and transport of radio-labeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study included flow rate, pH, i...

412

ORGANOTIN TOXICITY STUDIES CONDUCTED WITH SELECTED MARINE ORGANISMS AT EPA'S ENVIRONMENTAL RESEARCH LABORATORY, GULF BREEZE, FLORIDA  

EPA Science Inventory

Studies on effect of bis(tri-n-butyltin)oxide (TBTO) and other organotins on marine species have been conducted at the U.S. Environmental Protection Agency's laboratory at Gulf Breeze, Florida, since 1983. First studies were done on two species of algae, Skeletonema costatum and ...

413

Dietary Factors Modulate Helicobacter-Associated Gastric Cancer in Rodent Models  

PubMed Central

Since its discovery in 1982, the global importance of H. pylori-induced disease, particularly in developing countries, remains high. The use of rodent models particularly mice, and the unanticipated usefulness of the gerbil to study H. pylori pathogenesis have been used extensively to study the interactions of the host, the pathogen and the environmental conditions influencing the outcome of persistent H. pylori infection. Dietary factors in humans are increasingly recognized as being important factors in modulating progression and severity of H. pylori-induced gastric cancer. Studies using rodent models to verify and help explain mechanisms whereby various dietary ingredients impact disease outcome should continue to be extremely productive. PMID:24301796

Fox, James G.; Wang, Timothy C.

2014-01-01

414

Long-branch attraction phenomenon and the impact of among-site rate variation on rodent phylogeny.  

PubMed

The phylogenetic relationships among major lineages of rodents is one of the issues most debated by both paleontologists and molecular biologists. In the present study, we have analyzed all complete mammalian mitochondrial genomes available in the databases, including five rodent species (rat, mouse, dormouse, squirrel and guinea-pig). Phylogenetic analyses were performed on H-strand amino acid sequences by means of maximum-likelihood and on H-strand protein-coding and ribosomal genes by means of distance methods. Also, log-likelihood ratio tests were applied to different tree topologies under the assumption of rodent monophyly, paraphyly or polyphyly. The analyses significantly rejected rodent monophyly and showed the existence of two differentiated clades, one containing non-murids (dormouse, squirrel and guinea-pig) and the other containing murids (rat and mouse). Long-branch attraction between murids and the outgroups could not be responsible for the existence of two different rodent clades, as no significant differences in evolutionary rate have been observed, except in the case of the squirrel, which shows a lower rate. The impact of among-site rate variation models on the phylogeny of rodents has been evaluated using the gamma distribution model. Results have shown that relationships among rodents remained unchanged, and the general topology of the tree was not affected, even though some branches were not properly resolved, most likely due to a lack of fit between estimated and real rate heterogeneity parameters. PMID:11163975

Reyes, A; Pesole, G; Saccone, C

2000-12-23

415

The response of the Egyptian spiny mouse (Acomys cahirinus) and two other species of commensal rodents to anticoagulant rodenticides  

PubMed Central

The response of Acomys cahirinus to three anticoagulant rodenticides was investigated in the laboratory. In contrast to the other commensal rodents Rattus rattus and R. norvegicus, this species appears to be naturally very resistant to warfarin, difenacoum and brodifacoum. It is considered unlikely that anticoagulant poisons would be effective in the field for the control of A. cahirinus. PMID:7240734

Mahmoud, Wafeya; Redfern, R.

1981-01-01

416

Rodents as intermediate hosts of Hepatozoon ayorgbor (Apicomplexa: Adeleina: Hepatozoidae) from the African ball python, Python regius?  

Microsoft Academic Search

Two experimental trials were performed to elucidate the role of rodents in the life cycle of Hepatozoon species using snakes as intermediate hosts. In one trial, two ball pythons, Python regius Shaw, 1802 were force fed livers of laboratory mice previously inoculated with sporocysts of Hepatozoon ayorgbor Sloboda, Kamler, Bulantová, Votýpka et Modrý, 2007. Transmis- sion was successful in these

Michal Sloboda; Martin Kamler; Jana Bulantová; Jan Votýpka; David Modrý

417

Survey for hantaviruses, tick-borne encephalitis virus, and Rickettsia spp. in small rodents in Croatia.  

PubMed

In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunofluorescence assays (IIFT) and for nucleic acids by conventional (hantaviruses) and real-time RT-/PCRs (TBEV and Rickettsia spp.). A total of 25.5% (24/94) of the rodents from the mountainous area revealed specific antibodies against hantaviruses. In all, 21.3% (20/94) of the samples from the mountainous area and 29.0% (9/31) from the lowland area yielded positive results for either Puumala virus (PUUV) or Dobrava-Belgrade virus (DOBV) using a conventional RT-PCR. All processed samples (n=194) were negative for TBEV by IIFT or real-time RT-PCR. Serological evidence of rickettsial infection was detected in 4.3% (4/94) rodents from the mountainous region. Another 3.2% (3/94) rodents were positive for Rickettsia spp. by real-time PCR. None of the rodents (n=76) from the lowland area were positive for Rickettsia spp. by real-time PCR. Dual infection of PUUV and Rickettsia spp. was found in one M. glareolus from the mountainous area by RT-PCR and real-time PCR, respectively. To our knowledge, this is the first detection of Rickettsia spp. in small rodents from Croatia. Phylogenetic analyses of S- and M-segment sequences obtained from the two study sites revealed well-supported subgroups in Croatian PUUV and DOBV. Although somewhat limited, our data showed occurrence and prevalence of PUUV, DOBV, and rickettsiae in Croatia. Further studies are warranted to confirm these data and to determine the Rickettsia species present in rodents in these areas. PMID:24866325

Svoboda, Petra; Dobler, Gerhard; Markoti?, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinovi?, Lidija Cvetko; Tadin, Ante; Margaleti?, Josip; Essbauer, Sandra

2014-07-01

418

Prevalence and genetic diversity of bartonella strains in rodents from northwestern Mexico.  

PubMed

Abstract Bartonella infections were investigated in wild rodents from northwestern Chihuahua, Mexico. A total of 489 rodents belonging to 14 species were surveyed in four areas. Bartonella bacteria were cultured from 50.1% of rodent samples (245/489). Infection rates ranged from 0% to 83.3% per rodent species, with no significant difference between sites except for Cynomys ludovicianus. Phylogenetic analyses of the citrate synthase gene (gltA) of the Bartonella isolates revealed 23 genetic variants (15 novel and 8 previously described), clustering into five phylogroups. Three phylogroups were associated with Bartonella vinsonii subsp. vinsonii, B. vinsonii subsp. arupensis, and B. washoensis, respectively. The other two phylogroups were not genetically related to any known Bartonella species. The genetic variants and phylogenetic groups exhibited a high degree of host specificity, mainly at the genus and family levels. This is the first study that describes the genetic diversity of Bartonella strains in wild rodents from Mexico. Considering that some variants found in this study are associated with Bartonella species that have been reported as zoonotic, more investigations are needed to further understand the ecology of Bartonella species in Mexican wildlife and their implications for human health. PMID:25514119

Rubio, André V; Avila-Flores, Rafael; Osikowicz, Lynn M; Bai, Ying; Suzán, Gerardo; Kosoy, Michael Y

2014-12-01

419

Rodent Models and Behavioral Outcomes of Cervical Spinal Cord Injury  

PubMed Central

Rodent spinal cord injury (SCI) models have been developed to examine functional and physiological deficits after spinal cord injury with the hope that these models will elucidate information about human SCI. Models are needed to examine possible treatments and to understand histopathology after SCI; however, they should be considered carefully and chosen based on the goals of the study being performed. Contusion, compression, transection, and other models exist and have the potential to reveal important information about SCI that may be related to human SCI and the outcomes of treatment and timing of intervention. PMID:25309824

Geissler, Sydney A.; Schmidt, Christine E.; Schallert, Timothy

2014-01-01

420

Studying stars by going underground: the LUNA experiment at Gran Sasso Laboratory  

NASA Astrophysics Data System (ADS)

Cross sections of astrophysically relevant reactions are essential ingredients for element nucleosynthesis, energy generation and neutrino fluxes in stellar environments. The low value of such cross sections in the stellar energy range prevents their measurement in a laboratory at the Earth's surface where the signal to background ratio would be too small. The LUNA collaboration has exploited the unique features of background reduction offered by the rock overburden above the LNGS underground laboratory in order to study very important Hydrogen-burning reactions. Future perspectives include the installation of a MV machine underground to be able to study also Helium burning reactions.

Guglielmetti, Alessandra

2014-03-01

421

Molecular epidemiology of paramyxoviruses in Zambian wild rodents and shrews.  

PubMed

Rodents and shrews are known to harbour various viruses. Paramyxoviruses have been isolated from Asian and Australian rodents, but little is known about them in African rodents. Recently, previously unknown paramyxovirus sequences were found in South African rodents. To date, there have been no reports related to the presence and prevalence of paramyxoviruses in shrews. We found a high prevalence of paramyxoviruses in wild rodents and shrews from Zambia. Semi-nested reverse transcription-PCR assays were used to detect paramyxovirus RNA in 21 % (96/462) of specimens analysed. Phylogenetic analysis revealed that these viruses were novel paramyxoviruses and could be classified as morbillivirus- and henipavirus-related viruses, and previously identified rodent paramyxovirus-related viruses. Our findings suggest the circulation of previously unknown paramyxoviruses in African rodents and shrews, and provide new information regarding the geographical distribution and genetic diversity of paramyxoviruses. PMID:24189618

Sasaki, Michihito; Muleya, Walter; Ishii, Akihiro; Orba, Yasuko; Hang'ombe, Bernard M; Mweene, Aaron S; Moonga, Ladslav; Thomas, Yuka; Kimura, Takashi; Sawa, Hirofumi

2014-02-01

422

Gestational/perinatal chlorpyrifos exposure is not associated with autistic-like behaviors in rodents.  

PubMed

Although animal models cannot exactly replicate human psychiatric disorders, they may be useful to investigate whether the behaviors associated with certain exposures in animals parallel those observed in people. According to the most current version of the Diagnostic and Statistical Manual of Mental Disorders, autism is diagnosed based on (1) persistent deficits in social communication and social interaction; and (2) the presence of restricted, repetitive patterns of behavior, interests and activities. To address whether developmental chlorpyrifos (CPF) exposure was associated with the development of autistic behaviors, a literature search was conducted to identify studies in rats and mice involving gestational or early postnatal exposure to CPF or CPF oxon (CPO, the active metabolite of CPF) and subsequent behavioral testing to assess behaviors related to autism. A total of 13 studies conducted in six different laboratories were identified. Analysis of these studies found that perinatal CPF exposure was generally associated with (1) no effect or increased social communications; (2) no effect or increased social encounters; (3) no effect, reduced stereotypies, or conflicting findings on stereotypic behaviors; and (4) no effect or increased preference for novelty and reduced anxiety in novel environments. These behavioral findings are generally inconsistent with the types of behaviors that would be expected in children with clinical autism. Based on the results of this analysis of rodent model studies involving CPF/CPO exposure, it cannot be concluded that gestational and/or perinatal CPF exposure is likely to be associated with the development of autism-like behaviors in humans. PMID:24861450

Williams, Amy Lavin; DeSesso, John M

2014-07-01

423

[11C]Rhodamine-123: synthesis and biodistribution in rodents  

PubMed Central

Introduction Rhodamine-123 is a known substrate for the efflux transporter, P-glycoprotein (P-gp). We wished to assess whether rhodamine-123 might serve as a useful substrate for developing probes for imaging efflux transporters in vivo with positron emission tomography (PET). For this purpose, we aimed to label rhodamine-123 with carbon-11 (t1/2 = 20.4 min) and to study its biodistribution in rodents. Methods [11C]Rhodamine-123 was prepared by treating rhodamine-110 (desmethyl-rhodamine-123), with [11C]methyl iodide. The biodistribution of this radiotracer was studied with PET in wild-type mice and rats, in efflux transporter knockout mice, in wild-type rats pretreated with DCPQ (an inhibitor of P-gp) or with cimetidine (an inhibitor of organic cation transporters; OCT), and in P-gp knockout mice pretreated with cimetidine. Unchanged radiotracer in forebrain, plasma and peripheral tissues was also measured ex vivo at 30 min after radiotracer administration to wild-type and efflux transporter knockout rodents. Results [11C]Rhodamine-123 was obtained in 4.4% decay-corrected radiochemical yield from cyclotron-produced [11C]carbon dioxide. After intravenous administration of [11C]rhodamine-123 to wild-type rodents, PET and ex vivo measurements showed radioactivity uptake was very low in brain, but relatively high in some other organs such as heart, and especially liver and kidney. Inhibition of P-gp increased uptake in brain, heart, kidney and liver, but only by up to twofold. Secretion of radioactivity from kidney was markedly reduced by OCT knockout or pretreatment with cimetidine. Conclusions [11C]Rhodamine-123 was unpromising as a PET probe for P-gp function and appears to be a strong substrate of OCT in kidney. Cimetidine appears effective for blocking OCT in kidney in vivo. PMID:22898316

Bao, Xiaofeng; Lu, Shuiyu; Liow, Jeih-San; Morse, Cheryl L.; Anderson, Kacey; Zoghbi, Sami S.; Innis, Robert B.; Pike, Victor W.

2012-01-01

424

Bird's the Word: By Raising Chicks, Students Study Animals in the Laboratory  

ERIC Educational Resources Information Center

Most biology students have the opportunity to look at protozoa under the microscopes or keep mealworms in a bowl. They may manipulate the heart rate of "Daphnia" or calculate the respiration of plants. They may even grow corn in the spring or keep fish and a small rodent or two. But once the class hamster grows testy from being awakened every…

Barra, Paul A.

2002-01-01

425

Placentation in Sigmodontinae: a rodent taxon native to South America  

PubMed Central

Background Sigmodontinae, known as "New World rats and mice," is a large subfamily of Cricetidae for which we herein provide the first comprehensive investigation of the placenta. Methods Placentas of various gestational ages ranging from early pregnancy to near term were obtained for five genera, i.e. Necromys, Euryoryzomys, Cerradomys, Hylaeamys, and Oligoryzomys. They were investigated by means of histology, immunohistochemistry, a proliferation marker, DBA-lectin staining and transmission electron microscopy. Results The chorioallantoic placenta was organized in a labyrinthine zone, spongy zone and decidua and an inverted yolk sac persisted until term. The chorioallantoic placenta was hemotrichorial. The interhemal barrier comprised fetal capillary endothelium and three layers of trophoblast, an outermost, cellular layer and two syncytial ones, with interspersed trophoblast giant cells (TGC). In addition, accumulations of TGC occurred below Reichert's membrane. The junctional zone contained syncytial trophoblast, proliferative cellular trophoblast, glycogen cells and TGC that were situated near to the maternal blood channels. In three of the genera, TGC were also accumulated in distinct areas at the placental periphery. PAS-positive glycogen cells derived from the junctional zone invaded the decidua. Abundant maternal uNK cells with positive response to PAS, vimentin and DBA-lectin were found in the decidua. The visceral yolk sac was completely inverted and villous. Conclusion The general aspect of the fetal membranes in Sigmodontinae resembled that found in other cricetid rodents. Compared to murid rodents there were larger numbers of giant cells and in some genera these were seen to congregate at the periphery of the placental disk. Glycogen cells were found to invade the decidua but we did not identify trophoblast in the walls of the deeper decidual arteries. In contrast these vessels were surrounded by large numbers of uNK cells. This survey of wild-trapped specimens from five genera is a useful starting point for the study of placentation in an important subfamily of South American rodents. We note, however, that some of these rodents can be captive bred and recommend that future studies focus on the study of time dated pregnancies. PMID:21518439

2011-01-01

426

3 H and 90 Sr in urine radiobioassay intercomparison results from the intercomparison studies program at Oak Ridge National Laboratory: statistical analysis of laboratory performance  

Microsoft Academic Search

The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix\\u000a human urine quality-assurance\\/quality-control (QA\\/QC) samples to radiobioassay analysis laboratories. Samples are provided\\u000a to these laboratories as “single-blind” or “double-blind” unknowns, spiked with radioactive-solution standards at “low” levels\\u000a (e.g., 0.7–7 Bq g?1 for 3H and 0.7–7 Bq kg?1 for 90Sr). Participants use the results as a tool

Norman Bores; Michael K Schultz; J. M. Rankin; A. J. Denton; G. F. Payne

2009-01-01

427

RNAVLab: A virtual laboratory for studying RNA secondary structures based on grid computing technology.  

PubMed

As ribonucleic acid (RNA) molecules play important roles in many biological processes including gene expression and regulation, their secondary structures have been the focus of many recent studies. Despite the computing power of supercomputers, computationally predicting secondary structures with thermodynamic methods is still not feasible when the RNA molecules have long nucleotide sequences and include complex motifs such as pseudoknots. This paper presents RNAVLab (RNA Virtual Laboratory), a virtual laboratory for studying RNA secondary structures including pseudoknots that allows scientists to address this challenge. Two important case studies show the versatility and functionalities of RNAVLab. The first study quantifies its capability to rebuild longer secondary structures from motifs found in systematically sampled nucleotide segments. The extensive sampling and predictions are made feasible in a short turnaround time because of the grid technology used. The second study shows how RNAVLab allows scientists to study the viral RNA genome replication mechanisms used by members of the virus family Nodaviridae. PMID:19885376

Taufer, Michela; Leung, Ming-Ying; Solorio, Thamar; Licon, Abel; Mireles, David; Araiza, Roberto; Johnson, Kyle L

2008-11-01

428

RNAVLab: A virtual laboratory for studying RNA secondary structures based on grid computing technology  

PubMed Central

As ribonucleic acid (RNA) molecules play important roles in many biological processes including gene expression and regulation, their secondary structures have been the focus of many recent studies. Despite the computing power of supercomputers, computationally predicting secondary structures with thermodynamic methods is still not feasible when the RNA molecules have long nucleotide sequences and include complex motifs such as pseudoknots. This paper presents RNAVLab (RNA Virtual Laboratory), a virtual laboratory for studying RNA secondary structures including pseudoknots that allows scientists to address this challenge. Two important case studies show the versatility and functionalities of RNAVLab. The first study quantifies its capability to rebuild longer secondary structures from motifs found in systematically sampled nucleotide segments. The extensive sampling and predictions are made feasible in a short turnaround time because of the grid technology used. The second study shows how RNAVLab allows scientists to study the viral RNA genome replication mechanisms used by members of the virus family Nodaviridae. PMID:19885376

Taufer, Michela; Leung, Ming-Ying; Solorio, Thamar; Licon, Abel; Mireles, David; Araiza, Roberto; Johnson, Kyle L.

2009-01-01

429

Two-phase seed dispersal: linking the effects of frugivorous birds and seed-caching rodents.  

PubMed

Frugivorous birds disperse the seeds of many fruit-bearing plants, but the fate of seeds after defecation or regurgitation is often unknown. Some rodents gather and scatter hoard seeds, and some of these may be overlooked, germinate, and establish plants. We show that these two disparate modes of seed dispersal are linked in some plants. Rodents removed large (>25 mg) seeds from simulated bird feces (pseudofeces) at rates of 8-50%/day and scatter hoarded them in soil. Ants (Formica sibylla) also harvested some seeds and carried them to their nests. Rodents carried seeds 2.5+/-3.2 m to cache sites (maximum 12 m) and buried seeds at 8+/-7 mm depth. Enclosure studies suggest that yellow pine chipmunks (Tamias amoenus) and deer mice (Peromyscus maniculatus) made the caches. In spring, some seeds germinated from rodent caches and established seedlings, but no seedlings established directly from pseudofeces. This form of two-phase seed dispersal is important because each phase offers different benefits to plants. Frugivory by birds permits relatively long-range dispersal and potential colonization of new sites, whereas rodent caching moves seeds from exposed, low-quality sites (bird feces on the ground surface) to a soil environment that may help maintain seed viability and promote successful seedling establishment. PMID:15959820

Vander Wall, Stephen B; Kuhn, Kellie M; Gworek, Jennifer R

2005-09-01

430

Genotoxic Changes to Rodent Cells Exposed in Vitro to Tungsten, Nickel, Cobalt and Iron  

PubMed Central

Tungsten-based materials have been proposed as replacements for depleted uranium in armor-penetrating munitions and for lead in small-arms ammunition. A recent report demonstrated that a military-grade composition of tungsten, nickel, and cobalt induced a highly-aggressive, metastatic rhabdomyosarcoma when implanted into the leg muscle of laboratory rats to simulate a shrapnel wound. The early genetic changes occurring in response to embedded metal fragments are not known. In this study, we utilized two cultured rodent myoblast cell lines, exposed to soluble tungsten alloys and the individual metals comprising the alloys, to study the genotoxic effects. By profiling cell transcriptomes using microarray, we found slight, yet distinct and unique, gene expression changes in rat myoblast cells after 24 h metal exposure, and several genes were identified that correlate with impending adverse consequences of ongoing exposure to weapons-grade tungsten alloy. These changes were not as apparent in the mouse myoblast cell line. This indicates a potential species difference in the cellular response to tungsten alloy, a hypothesis supported by current findings with in vivo model systems. Studies examining genotoxic-associated gene expression changes in cells from longer exposure times are warranted. PMID:24619124

Bardack, Stephanie; Dalgard, Clifton L.; Kalinich, John F.; Kasper, Christine E.

2014-01-01

431

Genotoxic changes to rodent cells exposed in vitro to tungsten, nickel, cobalt and iron.  

PubMed

Tungsten-based materials have been proposed as replacements for depleted uranium in armor-penetrating munitions and for lead in small-arms ammunition. A recent report demonstrated that a military-grade composition of tungsten, nickel, and cobalt induced a highly-aggressive, metastatic rhabdomyosarcoma when implanted into the leg muscle of laboratory rats to simulate a shrapnel wound. The early genetic changes occurring in response to embedded metal fragments are not known. In this study, we utilized two cultured rodent myoblast cell lines, exposed to soluble tungsten alloys and the individual metals comprising the alloys, to study the genotoxic effects. By profiling cell transcriptomes using microarray, we found slight, yet distinct and unique, gene expression changes in rat myoblast cells after 24 h metal exposure, and several genes were identified that correlate with impending adverse consequences of ongoing exposure to weapons-grade tungsten alloy. These changes were not as apparent in the mouse myoblast cell line. This indicates a potential species difference in the cellular response to tungsten alloy, a hypothesis supported by current findings with in vivo model systems. Studies examining genotoxic-associated gene expression changes in cells from longer exposure times are warranted. PMID:24619124

Bardack, Stephanie; Dalgard, Clifton L; Kalinich, John F; Kasper, Christine E

2014-03-01

432

Comparative effect of the three rodenticides warfarin, difenacoum and brodifacoum on eight rodent species in short feeding periods.  

PubMed Central

Short laboratory feeding tests were carried out with the anticoagulants warfarin, difenacoum, and brodifacoum on a number of European rodent species: Clethrionomys glareolus, Microtus agrestis, M. arvalis, Apodemus flavicollis, A. sylvaticus, Mus musculus, Rattus rattus and R. norvegicus. It was found that the toxicity to all species was highest with brodifacoum and lowest with warfarin, and that only 0.005% brodifacoum would give a complete mortality in most species after one day's feeding. The potential of this compound for the control of microtine field rodents is suggested. PMID:7019316

Lund, M.

1981-01-01

433

Rodent evolution: back to the root.  

PubMed

Some 70 Ma, rodents arose along a branch of our own mammalian lineage. Today, about 40% of all mammalian species are rodents and are found in vast numbers on almost every continent. Not only is their proliferation extensive but also the rates of DNA evolution vary significantly among lineages, which has hindered attempts to reconstruct, especially the root of, their evolutionary history. The presence or absence of rare genomic changes, such as short interspersed elements (SINEs), are, however, independent of high molecular substitution rates and provide a powerful, virtually homoplasy-free source for solving such phylogenetic problems. We screened 12 Gb of rodent genomic information using whole-genome three-way alignments, multiple lineage-specific sequences, high-throughput polymerase chain reaction amplifications, and sequencing to reveal 65 phylogenetically informative SINE insertions dispersed over 23 rodent phylogenetic nodes. Eight SINEs and six indels provide significant support for an early association of the Mouse-related and Ctenohystrica (guinea pig and relatives) clades, the Squirrel-related clade being the sister group. This early speciation scenario was also evident in the genomewide distribution pattern of B1-related retroposons, as mouse and guinea pig genomes share six such retroposon subfamilies, containing hundreds of thousands of elements that are clearly absent in the ground squirrel genome. Interestingly, however, two SINE insertions and one diagnostic indel support an association of Ctenohystrica with the Squirrel-related clade. Lineage sorting or a more complex evolutionary scenario that includes an early divergence of the Squirrel-related ancestor and a subsequent hybridization of the latter and the Ctenohystrica lineage best explains such apparently contradictory insertions. PMID:20100942

Churakov, Gennady; Sadasivuni, Manoj K; Rosenbloom, Kate R; Huchon, Dorothée; Brosius, Jürgen; Schmitz, Jürgen

2010-06-01