Next-Generation Sequencing-Based Identification of as Causative Agent of High Mortality Disease in NOD.Cg-/SzJ (NSG) Mice.

NOD.Cg-/SzJ (NSG) mice, lacking many components of a mature immune system, are at increased risk of disease. General understanding of potential pathogens of these mice is limited.

Sex specific effects of buprenorphine on adult hippocampal neurogenesis and behavioral outcomes during the acute phase after pediatric traumatic brain injury in mice.

Traumatic brain injury (TBI) in children often causes cognitive and mental dysfunctions, as well as acute and chronic pain. Adult hippocampal neurogenesis plays a key role in cognition, depression, and pain. Adult hippocampal neurogenesis can be modulated by genetic and environmental factors, such as TBI and opioids.

Sex-Specific Effects of Buprenorphine on Endoplasmic Reticulum Stress, Abnormal Protein Accumulation, and Cell Loss After Pediatric Mild Traumatic Brain Injury in Mice.

Traumatic brain injury (TBI) in children often leads to poor developmental outcomes attributable to progressive cell loss caused by secondary injuries, including endoplasmic reticulum (ER) stress. Buprenorphine (BPN) is commonly used in children for pain management; however, the effects of BPN on ER stress in the pediatric population are still inconclusive. This study investigated the sex-specific effects of BPN on ER stress, abnormal protein accumulation, and cell loss in a mouse impact acceleration model of pediatric TBI.

History of the National Academies of Sciences, Engineering, and Medicine's Institute for Laboratory Animal Research.

The Institute for Laboratory Animal Research (ILAR) was created within the National Academies of Sciences, Engineering, and Medicine (National Academies) in 1953 when biomedical research using animals was in its infancy in terms of quantity, quality, complexity, sophistication, and care. Over the intervening 69 years, ILAR has witnessed unprecedented growth, followed by unprecedented decline, and then regrowth in usage of specific species and models and an overall shift in experimental burden away from larger to smaller species (ie, mice, fish, and rats). ILAR has contributed much to the evolution of necessary research using animals and animal models for the benefit of humans, animals, and the environment and to the development and implementation of humane principles and standards for care and use of research animals.

Sex specific effects of buprenorphine on behavior, astrocytic opioid receptor expression and neuroinflammation after pediatric traumatic brain injury in mice.

Children who suffered traumatic brain injury (TBI) often experience acute and chronic pain, which is linked to a poor quality of life. Buprenorphine (BPN) is commonly used to treat moderate to severe persistent pain in children, however, the efficacy and safety profile of BPN in the pediatric population is still inconclusive. This study investigated the sex-specific effects of BPN on body weight, motor coordination and strength, expression of opioid receptors in the white matter astrocytes, and neuroinflammation in a mouse impact acceleration model of pediatric TBI.

Degenerative Myelopathy and Neuropathy in NOD./SzJ (NSG) Mice Caused by Lactate Dehydrogenase-Elevating Virus (LDV).

Following implantation of patient-derived xenograft (PDX) breast carcinomas from three separate individuals, 33/51 female NOD./SzJ (NSG) mice presented with progressive, unilateral to bilateral, ascending hindlimb paresis to paralysis. Mice were mildly dehydrated, in thin to poor body condition, with reduced to absent hindlimb withdrawal reflex and deep pain sensation.

Variation in Bacterial Contamination of Microisolation Cage Tops According to Rodent Species and Housing System.

The recommends sanitizing cage components, including microisolation cage tops (MCT), at a minimum of every 2 wk. Previously published data demonstrated that mouse MCT microbial loads do not increase until at least 2 wk and that sanitation can be delayed past 2 wk. How microbial loads differ on mouse compared with rat MCT, as well as across different ventilation systems, remains unclear.

Naturally occurring disseminated group B streptococcus infections in postnatal rats.

Group B Streptococcus (Streptococcus agalactiae, GBS) is a gram-positive commensal and occasional opportunistic pathogen of the human vaginal, respiratory, and intestinal tracts that can cause sepsis, pneumonia, or meningitis in human neonates, infants, and immunosuppressed persons. We report here on a spontaneous outbreak of postnatal GBS-associated disease in rats. Ten of 26 (38.

Polytetrafluoroethylene toxicosis in recently hatched chickens (Gallus domesticus).

Two groups of chickens (Gallus domesticus; White Leghorn; age, 4 d and 2 wk) housed in a university research vivarium were found dead or moribund without prior signs of illness. The overall mortality rates were 92.3% (60 of 65 birds) for the 4-d-old birds and 80% (8 of 10) for the 2-wk-old birds.

Angiotensin II-dependent persistent podocyte loss from destabilized glomeruli causes progression of end stage kidney disease.

Podocyte depletion is a major mechanism driving glomerulosclerosis. Progression is the process by which progressive glomerulosclerosis leads to end stage kidney disease (ESKD). In order to determine mechanisms contributing to persistent podocyte loss, we used a human diphtheria toxin transgenic rat model.

Bacteria from drinking water supply and their fate in gastrointestinal tracts of germ-free mice: a phylogenetic comparison study.

Microorganisms in drinking water sources may colonize in gastrointestinal (GI) tracts and this phenomenon may pose a potential health risk especially to immunocompromised population. The microbial community diversity of the drinking water was compared with the GI tracts of the mice using phylogenetic and statistical analyses of 16S rRNA gene sequences. A group of germ-free mice were fed with drinking water from public water supply that passed through an automated watering system with documented biofilm accumulation.

Principles of bone marrow transplantation (BMT): providing optimal veterinary and husbandry care to irradiated mice in BMT studies.

Bone marrow transplantation (BMT) is the treatment of choice for many leukemias, solid tumors, and metabolic diseases. The field of bone marrow research is highly dependent on in vivo experimentation, because in vitro techniques do not mimic these complicated in vivo systems. Therefore, understanding the medical and husbandry care needs of these transiently immunodeficient bone marrow recipient animals is crucial for researchers, veterinary and animal care personnel.

Quantification, distribution, and possible source of bacterial biofilm in mouse automated watering systems.

The use of automated watering systems for providing drinking water to rodents has become commonplace in the research setting. Little is known regarding bacterial biofilm growth within the water piping attached to the racks (manifolds). The purposes of this project were to determine whether the mouse oral flora contributed to the aerobic bacterial component of the rack biofilm, quantify bacterial growth in rack manifolds over 6 mo, assess our rack sanitation practices, and quantify bacterial biofilm development within sections of the manifold.

Genetic modulation of hormone levels and life span in hybrids between laboratory and wild-derived mice.

Previously we showed that mouse stocks derived from wild-caught progenitors are long-lived relative to genetically heterogeneous mice derived from laboratory-adapted strains. Here we replicate this life-span effect, and show that F2 hybrids between wild-derived and laboratory-derived stocks have intermediate survival patterns. Moreover, wild-derived mice are small, lean, and slow to mature, and have low serum insulin-like growth factor-I (IGF-I) relative to genetically heterogeneous mice.

Technique for performance and evaluation of parapharyngeal hypophysectomy in mice.

Mice at our institution were hypophysectomized to evaluate the effects of growth hormone on the expression of a transfected human factor IX gene. The hypophysectomy was performed in-house by using a parapharyngeal approach modified from previously published surgical techniques. Modifications included: 1) choice of ketamine-xylazine and isoflurane for anesthesia, with butorphanol for postoperative analgesia; 2) use of a V-trough for positioning mice correctly and consistently; 3) selection of increasing sizes of dental burrs to create a foramen in the cranial base through which the pituitary gland was removed; and 4) disuse of a tracheotomy for airway patency.

Podocyte depletion causes glomerulosclerosis: diphtheria toxin-induced podocyte depletion in rats expressing human diphtheria toxin receptor transgene.

Glomerular injury and proteinuria in diabetes (types 1 and 2) and IgA nephropathy is related to the degree of podocyte depletion in humans. For determining the causal relationship between podocyte depletion and glomerulosclerosis, a transgenic rat strain in which the human diphtheria toxin receptor is specifically expressed in podocytes was developed. The rodent homologue does not act as a diphtheria toxin (DT) receptor, thereby making rodents resistant to DT.

Assessment of bacterial contamination of drinking water provided to mice.

The objective of this study was to evaluate whether an 240-ml water bottle provided to individually housed mice would remain potable for a 2-week interval (based on absence of coliforms). The study used inbred C57BL/6 mice and CB6F1 x C3D2F1 hybrid mice. Test groups were assigned to minimize the variables of strain, caging type (non-ventilated static versus ventilated) and building location.

Longer life spans and delayed maturation in wild-derived mice.

Nearly all the experimental mice used in aging research are derived from lineages that have been selected for many generations for adaptation to laboratory breeding conditions and are subsequently inbred. To see if inbreeding and laboratory adaptation might have altered the frequencies of genes that influence life span, we have developed three lines of mice (Idaho [Id], Pohnpei [Po], and Majuro [Ma]) from wild-trapped progenitors, and have compared them with a genetically heterogeneous mouse stock (DC) representative of the laboratory-adapted gene pool. Mean life span of the Id stock exceeded that of the DC stock by 24% (P < 0.

Subcutaneous hemangiosarcomas in a rhesus macaque (Macaca mulatta).

Hemangiosarcoma is a malignant tumor of vascular endothelial cell origin. The occurrence of hemangiosarcoma in nonhuman primates has been rarely documented. An adult male rhesus monkey was reported having a firm subcutaneous swelling, approximately 4.

Altered podocyte structure in GLEPP1 (Ptpro)-deficient mice associated with hypertension and low glomerular filtration rate.

Glomerular epithelial protein 1 (GLEPP1) is a receptor tyrosine phosphatase present on the apical cell surface of the glomerular podocyte. The GLEPP1 gene (PTPRO:) was disrupted at an exon coding for the NH(2)-terminal region by gene targeting in embryonic stem cells. Heterozygote mating produced the expected genotypic ratio of 1:2:1, indicating that the Ptpro(-/-) genotype does not lead to embryonic or neonatal lethality.

Mouse () stocks derived from tropical islands: new models for genetic analysis of life-history traits.

Founder effects, together with access to unoccupied ecological niches, may allow rodent populations on isolated islands to evolve constellations of life-history traits that distinguish them from their mainland relatives, for example in body size, litter size, and longevity. In particular, low intrinsic mortality risks on islands with reduced predator numbers and not subject to harsh winter climates may in principle support the development of stocks with extended longevity. Conversely, the conditions under which laboratory rodents are typically bred are thought to select for genotypes that produce large, rapidly maturing races with high early reproductive rates but diminished longevity.

Exotic mice as models for aging research: polemic and prospectus.

Most gerontological research using rodent models employs inbred strains, or F1 hybrids derived from them, rather than populations of genetically heterogeneous individuals. This study presents the argument that reliance on genetically homogeneous rodents, though sanctioned by tradition, may not be ideal for many sorts of investigations, and that use of heterogeneous mice and rats would allow researchers to reach robust conclusions that were less likely to reflect strain-specific idiosyncrasies. Segregating stocks, bred by backcross, F2 cross, or four-way cross procedures, would be an improvement over inbred and F1 stocks, providing inexpensive, arbitrarily large, and reproducible populations of genetically diverse test subjects.