Polymerase Chain Reaction on In-cage Filter Paper at Different Time Points to Detect Helicobacter spp.

Helicobacter spp. infections in mice can have broad-ranging effects on gastrointestinal, reproductive, and immune systems. This can introduce significant confounding variables for research and may reduce scientific rigor. Screening mouse colonies for Helicobacter species can be accomplished via noninvasive PCR testing on filter paper placed in animal-free dirty bedding sentinel cages. In our facility, one tablespoon of dirty bedding from each cage on a rack is added to a designated sentinel cage every 3 wk at cage change, and PCR testing is performed on in-cage filter paper quarterly. We hypothesized that cages that received Helicobacter spp.-positive bedding at later time points would have a lower detection rate of Helicobacter spp. with PCR testing compared with cages that received positive bedding at earlier time points due to the filter paper becoming saturated. To determine if screening would be able to detect one positive row of cages on a rack, 9 tablespoons of Helicobacter-positive bedding and 71 tablespoons of negative bedding were added at the 3-, 6-, or 9-wk time points to 14 empty sentinel cages per time point. Negative bedding was added every 3 wk to cages not scheduled to receive positive bedding. Negative controls received 80 tablespoons of negative bedding and positive controls received 80 tablespoons of positive bedding at each time point. Filter paper was tested via PCR for Helicobacter spp. at 12 wk. All positive controls tested positive, and all negative controls tested negative. Two 3-wk cages, two 6-wk cages, and three 9-wk cages were positive, indicating no difference between time points. This resulted in a 16.7% Helicobacter spp. detection rate. These results indicate that PCR on in-cage filter paper may not be reliable in detecting low levels of Helicobacter spp. nucleic acid in dirty bedding.

Comparison of Plenum and Cage-level Filter Exhaust Dust PCR Testing to Soiled Bedding Sentinel Mice (Mus musculus) on an IVC Rack.

The use of soiled-bedded sentinels (SBSs) has historically been the standard for colony health surveillance monitoring at our institution. With the advent of newer technologies in which dust collected from filters is tested by PCR, we compared traditional SBS with PCR testing of both exhaust air dust collected from a filter in the downstream vertical plenum (exhaust dust test [EDT]) and the SBS cage-level exhaust filter (SCEF). Our hypothesis was that both methods of filter testing would identify more pathogens than SBS testing. Twenty-five individually ventilated mouse racks that used disposable caging were sanitized and placed into rotation. Rack plenums were tested by PCR to verify negative results before the study start. Exhaust dust collection media were placed in the exhaust plenum (n = 25). SBS cages were placed on each side of the rack with 2 mice per cage (n = 42 mice), with the remaining cage slots occupied by research animals. At each triweekly cage change, the exhaust air filters were carefully removed from the cage top, placed in sterile 50-mL conical tubes, and pooled for submission. After 3 mo, the SBS mice were tested via serology for bacterial and viral agents and by PCR for Helicobacter species, pinworms, and ectoparasites. In addition, the EDT filter and SCEF were collected for PCR to evaluate for the same agents. Our results indicate that the SCEF consistently detected agents more frequently than the EDT filter placed in the plenum and that the EDT filter media detected agents more frequently than did the SBS mice. Our data suggest that both PCR methods of detection are superior to SBS for individually ventilated disposable rodent cages and that the SCEF is superior to EDT. These data supported our movement of institution toward environmental monitoring as a method of rodent colony health surveillance.

Regenerative Engineering of a Biphasic Patient-Fitted Temporomandibular Joint Condylar Prosthesis.

Regenerative medicine approaches to restore the mandibular condyle of the temporomandibular joint (TMJ) may fill an unmet patient need. In this study, a method to implant an acellular regenerative TMJ prosthesis was developed for orthotopic implantation in a pilot goat study. The scaffold incorporated a porous, polycaprolactone-hydroxyapatite (PCL-HAp, 20wt% HAp) 3D printed condyle with a cartilage-matrix-containing hydrogel. A series of material characterizations was used to determine the structure, fluid transport, and mechanical properties of 3D printed PCL-HAp. To promote marrow uptake for cell seeding, a scaffold pore size of 152 ± 68 µm resulted in a whole blood transport initial velocity of 3.7 ± 1.2 mm·s-1 transported to the full 1 cm height. The Young's modulus of PCL was increased by 67% with the addition of HAp, resulting in a stiffness of 269 ± 20 MPa for etched PCL-HAp. In addition, the bending modulus increased by 2.06-fold with the addition of HAp to 470 MPa for PCL-HAp. The prosthesis design with an integrated hydrogel was compared with unoperated contralateral control and no-hydrogel group in a goat model for 6 months. A guide was used to make the condylectomy cut, and the TMJ disc was preserved. MicroCT assessment of bone suggested variable tissue responses with some regions of bone growth and loss, although more loss may have been exhibited by the hydrogel group than the no-hydrogel group. A benchtop load transmission test suggested that the prosthesis was not shielding load to the underlying bone. Although variable, signs of neocartilage formation were exhibited by Alcian blue and collagen II staining on the anterior, functional surface of the condyle. Overall, this study demonstrated signs of functional TMJ restoration with an acellular prosthesis. There were apparent limitations to continuous, reproducible bone formation, and stratified zonal cartilage regeneration. Future work may refine the prosthesis design for a regenerative TMJ prosthesis amenable to clinical translation.

Bringing psychologists to the fight against deep poverty.

This article describes the history, inspiration, goals, and outputs of the 2019 APA Presidential Initiative on Deep Poverty. Historically, psychologists have contributed to understanding the causes and consequences of poverty, as well as in interventions to ameliorate its effects. Less attention has been paid, however, to psychologists' unique contributions to studying and ending deep poverty, despite psychology's obvious relevance to the topic. As such, a working group was formed to develop the Deep Poverty Initiative (DPI), which had 3 main goals to engage psychologists in the fight against deep poverty: (a) change attitudes and perceptions about people living in deep poverty, (b) change policy to increase support for safety-net programs, and (c) change practices by increasing the use of psychological science and practice to build the capacity of poverty-serving organizations. First, 5 main themes from the psychological literature on deep poverty were identified by the DPI working group as crucial to changing attitudes. Compared to poverty, deep poverty was found to be especially dehumanizing, difficult to exit, and complex to solve, while also causing additional physical and psychological harm and obscuring human strengths. With this information as a basis, the working group mobilized psychologists to use the psychological science, along with their skills and positions within communities, to achieve the remaining goals of the initiative. Specific outputs, lessons learned, and suggestions for future work to continue to bring psychologists to the fight against deep poverty are given. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Evaluation of Peripheral Blood Markers as Early Endpoint Criteria in Guinea Pigs (Cavia porcellus) when Testing Tuberculosis Vaccine Candidates.

The guinea pig model of tuberculosis is used extensively to assess the efficacy of novel tuberculosis vaccines. There are established parameters to determine vaccine efficacy in this model, but the science community currently lacks established biomarkers for early detection and monitoring of experimental disease in guinea pigs. To define a set of biomarkers that could be used as benchmarks for disease progression and early endpoint criteria, we assessed serum biochemical and hematology parameters in 2 groups of guinea pigs-one vaccinated with the attenuated Mycobacterium bovis vaccine strain (BCG) and one sham-vaccinated with saline-and then experimentally infected with a virulent strain of Mycobacterium tuberculosis. After infection, WBC showed the strongest differences between saline-inoculated and vaccinated animals, with more subtle changes in other serum biochemical parameters, including ALT and ALP. Therefore, this study provides a starting point for evaluating the utility of blood values as possible early endpoint criteria in the guinea pig model of tuberculosis.

Microgroove and Collagen-poly(ε-caprolactone) Nanofiber Mesh Coating Improves the Mechanical Stability and Osseointegration of Titanium Implants.

The effect of depositing a collagen (CG)-poly-ε-caprolactone (PCL) nanofiber mesh (NFM) at the microgrooves of titanium (Ti) on the mechanical stability and osseointegration of the implant with bone was investigated using a rabbit model. Three groups of Ti samples were produced: control Ti samples where there were no microgrooves or CG-PCL NFM, groove Ti samples where microgrooves were machined on the circumference of Ti, and groove-NFM Ti samples where CG-PCL NFM was deposited on the machined microgrooves. Each group of Ti samples was implanted in the rabbit femurs for eight weeks. The mechanical stability of the Ti/bone samples were quantified by shear strength from a pullout tension test. Implant osseointegration was evaluated by a histomorphometric analysis of the percentage of bone and connective tissue contact with the implant surface. The bone density around the Ti was measured by micro-computed tomography (µCT) analysis. This study found that the shear strength of groove-NFM Ti/bone samples was significantly higher compared to control and groove Ti/bone samples (p < 0.05) and NFM coating influenced the bone density around Ti samples. In vivo histomorphometric analyses show that bone growth into the Ti surface increased by filling the microgrooves with CG-PCL NFM. The study concludes that a microgroove assisted CG-PCL NFM coating may benefit orthopedic implants.

Blood profiles in unanesthetized and anesthetized guinea pigs (Cavia porcellus).

The guinea pig is a common animal model that is used in biomedical research to study a variety of systems, including hormonal and immunological responses, pulmonary physiology, corticosteroid response and others. However, because guinea pigs are evolutionarily a prey species, they do not readily show behavioral signs of disease, which can make it difficult to detect illness in a laboratory setting. Minimally invasive blood tests, such as complete blood counts and plasma biochemistry assays, are useful in both human and veterinary medicine as an initial diagnostic technique to rule in or rule out systemic illness. In guinea pigs, phlebotomy for such tests often requires that the animals be anesthetized first. The authors evaluated hematological and plasma biochemical effects of two anesthetic agents that are commonly used with guinea pigs in a research setting: isoflurane and a combination of ketamine and xylazine. Hematological and plasma biochemical parameters were significantly different when guinea pigs were under either anesthetic, compared to when they were unanesthetized. Plasma proteins, liver enzymes, white blood cells and red blood cells appeared to be significantly altered by both anesthetics, and hematological and plasma biochemical differences were greater when guinea pigs were anesthetized with the combination of ketamine and xylazine than when they were anesthetized with isoflurane. Overall these results indicate that both anesthetics can significantly influence hematological and plasma biochemical parameters in guinea pigs.

Blood collection in the guinea pig (Cavia porcellus).

Guinea pigs are useful animal models for the study of many human diseases including diabetes mellitus and infectious diseases. Often, these studies involve collecting blood samples of considerable volume. This column describes safe techniques for restraint and blood collection from the jugular vein and cranial vena cava from alert and anesthetized guinea pigs.

Safety and immunogenicity of a combination measles, mumps, rubella and varicella vaccine (ProQuad).

BACKGROUND: A combination measles, mumps, rubella, and varicella vaccine (ProQuad, Merck & Co., Inc, West Point, PA) was evaluated in five clinical trials. Use of ProQuad would result in fewer injections for children and would facilitate universal immunization against all four diseases. OBJECTIVE: To describe the combined results obtained from the studies conducted during the clinical development program for ProQuad. METHODS: A total of 5833 healthy children, 12-23 months of age, and 399 healthy children, 4-6 years of age, received 1 or 2 doses of ProQuad in five controlled clinical trials. M-M-R II and VARIVAX were used as the control for most studies. Safety was evaluated for six weeks postvaccination and immunogenicity was assessed six weeks after each dose by a sensitive assay (ELISA or gpELISA). RESULTS: A single dose of ProQuad in 12- to 23-month-old children was shown to be as immunogenic as a single dose of M-M-R II and VARIVAX and was generally well tolerated. ProQuad can be used concomitantly with other vaccines (hepatitis B and Hoemophilus influenzoe b). A higher rate of fever was reported after 1 dose of ProQuad compared to M-M-R II and VARIVAX, but fever episodes were transient without long-term sequelae. Both a 2-dose regimen of ProQuad in 12- to 23-month-olds and use of ProQuad in place of M-M-R II at 4-6 years were shown to be immunogenic and well tolerated. The incidence of adverse experiences following a second dose of ProQuad was lower than that following the initial dose. CONCLUSIONS: A single dose of ProQuad is as immunogenic as M-M-R II and VARIVAX and is well tolerated in a 1- or 2-dose schedule. ProQuad should easily fit into the routine immunization schedule.

The safety and immunogenicity of a quadrivalent measles, mumps, rubella and varicella vaccine in healthy children: a study of manufacturing consistency and persistence of antibody.

BACKGROUND: This clinical trial was conducted to demonstrate that each of 3 consistency lots of a combined measles, mumps, rubella and varicella vaccine (MMRV) would be well tolerated, induce clinically acceptable and similar immune responses to each antigen and induce immune responses similar to measles, mumps and rubella vaccine (MMR) administered concomitantly with varicella vaccine (V). An additional objective was to evaluate the persistence of antibodies 1 year postvaccination. METHODS: Study participants 12 to 23 months of age received a single injection of either one of 3 consistency lots of MMRV or MMR + V administered at separate injection sites. RESULTS: A total of 3,928 healthy children were enrolled at study sites in the United States and Canada. Immune responses to measles, mumps, rubella and varicella in children immunized with each of 3 lots of MMRV were similar and the combined response to all 3 lots was comparable to that of the control group. The 1-year antibody persistence rates for measles, mumps, rubella and varicella viruses were each greater than 95% and comparable among the recipients of the 3 consistency lots of MMRV and the control group. All vaccines were generally well tolerated during the 42 days after vaccination and the overall incidence of adverse experiences was comparable between recipients of MMRV and MMR + V. Rates of fever (temperature >or=38.9 degrees C oral equivalent or tactile) were greater in recipients of MMRV than in recipients of MMR + V (39.1% versus 33.1%, P = 0.001). Fevers were transient and there was no difference in the incidence of febrile seizures. CONCLUSIONS: MMRV was generally well tolerated and had comparable immunogenicity and overall safety profiles to MMR + V administered concomitantly. Long-term persistence of antibodies after receipt of MMRV is expected based on similar antibody titers against all 4 antigens 1 year postvaccination compared with recipients of MMR and V.

Dose-response study of a quadrivalent measles, mumps, rubella and varicella vaccine in healthy children.

BACKGROUND: A combined measles, mumps, rubella and varicella (MMRV) vaccine would facilitate universal immunization against 4 diseases by decreasing the number of injections and thus enhancing compliance and coverage rates. If a second dose of varicella vaccine were to be recommended, MMRV could be used to administer a routine second dose of M-M-RII with the added advantage of boosting varicella-zoster virus (VZV) antibody titers. METHODS: Subjects 12-23 months of age received a single injection of 1 of 3 lots of an MMRV vaccine (ProQuad) containing high, middle or low VZV potency, or VARIVAX given concomitantly with M-M-RII. Recipients of MMRV received a second injection of MMRV approximately 90 days later. RESULTS: We enrolled 1559 subjects in the study. Antibody response rates to VZV 6 weeks after 1 injection of high potency MMRV (88.6%) or 2 injections of MMRV of any varicella potency (99.7-100%) were similar to the response rates after concomitant administration of M-M-RII and VARIVAX (93.1%). The second injection of MMRV boosted VZV antibody titers. Antibody responses to measles, mumps and rubella were >or=98%, similar to the control, after 1 or 2 injections of MMRV. MMRV was generally well-tolerated during the 42 days after vaccination. CONCLUSIONS: One injection of high potency MMRV resulted in antibody responses to the 4 vaccine components equivalent to those found after concomitant administration of M-M-RII and VARIVAX. A second injection of MMRV resulted in a significant boost in VZV antibody. This boost may translate into enhanced immunogenicity against varicella, which is known to correlate with increased protection.