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Rodents emit ultrasonic vocalizations (USVs) above the human hearing threshold of ~ 20 kHz to communicate emotional states and to coordinate their social interactive behavior. Twenty-two kHz USVs emitted by adult rats have been reported in a variety of aversive social and behavioral situations. They occur not only under painful or restraining conditions but can also be evoked by gentle cutaneous touch or airflow. This study aimed to test if placement of a human hand in a cage can evoke 22-kHz USVs. It was found that 36% of the adult male Sprague-Dawley and 13% of the adult male Wistar Han rats emitted 22-kHz USVs when a gloved hand was introduced into the cages. Average vocalization onset latencies were 5.0 ± 4.4 s (Sprague-Dawley) and 7.4 ± 4.0 s (Wistar Han) and the USVs had a stable frequency (22 kHz) across the calls, ranging from 0.1 to 2.3 seconds in duration. Surprisingly, no 22-kHz USVs were found in any female Wistar Han rats tested. To further explore the mechanisms underlying this observation, we compared retinal function, basal serum corticosterone, and testosterone levels between the 22-kHz USV responders and non-responders. None of these parameters or endpoints showed any significant differences between the two cohorts. The results suggest that the introduction of a gloved-hand inside the cage can trigger adult male albino rats to emit 22-kHz ultrasonic vocalizations. This response should be considered in USV studies and animal welfare. [ABSTRACT FROM AUTHOR]

The use of Wistar Han (WH) rats in regulatory toxicology studies, including juvenile animal studies, is increasing. The current study was performed to characterize femur development in neonatal and juvenile WH rats. Beginning on postnatal day (PND) 4 through PND 50, groups of WH rats (n = 5/sex) were evaluated for the development and ossification of the femur by Alizarin Red S staining, micro‐computed tomography (micro‐CT) imaging, microscopic examination, and Collagen X immunostaining. The focus of these evaluations was limited to the proximal femur including the head, neck, greater trochanter, lesser trochanter, and shaft. Through the multiple methods utilized, it was determined that the femoral neck is the first structure of the proximal femur to ossify, which occurs between PND 15 and 20. The femoral head and greater trochanter begin to separate on PND 15 with separation completing on PND 25 (both still composed of cartilage). Evidence of mineralization and ossification of these structures is apparent at PND 25, with a progressive increase with age, reaching adult‐like morphology by PND 40. This work has provided a thorough characterization of postnatal femur development in WH rats to help inform bone and femur effects in juvenile toxicity studies as well as the design of investigative studies. [ABSTRACT FROM AUTHOR]

Background: Although multiple randomized controlled trials (RCTs) and systematic review and meta-analysis were performed to investigate the efficiency and safety of nonsteroidal anti-inflammatory drugs (NSAIDs) and opioids in the treatment of acute renal colic, the therapeutic regimen of renal colic is still controversial. Therefore, the aim of this study was to derive a more concise comparison of the effectiveness and safety between NSAIDs and opioids in the treatment for patients with acute renal colic by a systematic review and meta-analysis. Design: We searched PubMed, Embase, and Cochrane Central Register of controlled trials for seeking eligible studies. The pooled mean difference (MD) or risk ratio (RR) with 95% confidence interval (CI) was calculated using the random effects model. The primary outcome was assessed according to the Grading of Recommendations Assessment, Development and Evaluation. Results: A total of 18 studies involving 3,121 participants were included in the systematic review and meta-analysis. No significant difference between the NSAID and opioid groups was observed, with changes in the visual analog scale (VAS) at 0–30 min (MD = 0.79, 95% CI: −0.51, 2.10). NSAIDs in the form of intravenous administration (IV) had no better effect on the changes in the VAS at 0–30 min, when compared to opioids (MD = 1.25, 95% Cl: −4.81, 7.3). The NSAIDs group in the form of IV had no better outcome compared to the opioids group, as well as the VAS at 30 min (MD = −1.18, 95% Cl: −3.82, 1.45; MD = −2.3, 95% Cl: −5.02, 0.42, respectively). Moreover, similar results of this outcome were also seen with the VAS at 45 min (MD = −1.36, 95% Cl: −5.24, 2.52). Besides, there was a statistical difference in the incidence of later rescue (RR = 0.76, 95% CI: 0.66, 0.89), drug-related adverse events (RR = 0.44, 95% CI: 0.27, 0.71), and vomiting (RR = 0.68, 95% CI: 0.49, 0.96). Conclusion: There is no significant difference between the NSAIDs and opioids in the treatment of renal colic in many outcomes (e.g., the VAS over different periods using different injection methods at 30 and 60 min), which has been focused on in this study. However, the patients who were treated using NSAIDs by clinicians can benefit from fewer side effects. [ABSTRACT FROM AUTHOR]

In oncology research, while xenograft tumor models are easily visualized and humane endpoints can be clearly defined, metastatic tumor models are often based on more subjective clinical observations as endpoints. This study aimed at identifying objective non-invasive criteria for predicting imminent distress and mortality in metastatic lung tumor-bearing mice. BALB/c and C57BL/6 mice were inoculated with CT26 or B16F10 cells, respectively. The mice were housed in Vium smart cages to continuously monitor and stream respiratory rate and locomotion for up to 28 days until scheduled euthanasia or humane endpoint criteria were met. Body weight and body temperature were measured during the study. On days 11, 14, 17 and 28, lungs of subsets of animals were microCT imaged in vivo to assess lung metastasis progression and then euthanized for lung microscopic evaluations. Beginning at day 21, most tumor-bearing animals developed increased respiratory rates followed by decreased locomotion 1–2 days later, compared with the baseline values. Increases in respiratory rate did not correlate to surface tumor nodule counts or lung weight. Body weight measurement did not show significant changes from days 14–28 in either tumor-bearing or control animals. We propose that increases in respiratory rate (1.3–1.5 X) can be used to provide an objective benchmark to signal the need for increased clinical observations or euthanasia. Adoption of this novel humane endpoint criterion would allow investigators time to collect tissue samples prior to spontaneous morbidity or death and significantly reduce the distress of mice in the terminal stages of these metastatic lung tumor models. [ABSTRACT FROM AUTHOR]

Orphan genes are genetic innovations that lack homologs in other lineages. Orphan genes can rapidly originate and become substantially functional, yet the mechanisms underlying their origins are still largely unknown in plants. Here, we investigated the origin of orphan genes in the Oryza sativa ssp. japonica "Nipponbare" genome using genome‐wide comparisons with 10 closely related Oryza species. We identified a total of 37 orphan genes in the Nipponbare genome that show short sequence lengths, elevated GC content, and absence of introns. Interestingly, half of the identified orphan genes originated by way of a distinctive mechanism that involved the generation of new coding sequences through independent and rapid divergence within the inserted transposable element. Our results provide valuable insight into genetic innovations in the model rice genome that formed on a very short timescale. [ABSTRACT FROM AUTHOR]

Clinical use of the chemotherapeutic agent vincristine (VCR) is limited by chemotherapy-induced peripheral neuropathy (CiPN). A new formulation of VCR encapsulated by nanoparticles has been proposed and developed to alleviate CiPN. We hypothesized in nonclinical animals that the nanoparticle drug would be less neurotoxic due to different absorption and distribution properties to the peripheral nerve from the unencapsulated free drug. Here, we assessed whether VCR encapsulation in nanoparticles alleviates CiPN using behavioral gait analysis (CatWalk), histopathologic and molecular biological (RT-qPCR) approaches. Adult male C57BL/6 mice were assigned to 3 groups (empty nanoparticle, nano-VCR, solution-based VCR, each n = 8). After 15 days of dosing, animals were euthanized for tissue collection. It was shown that intraperitoneal administration of nano-VCR (0.15 mg/kg, every other day) and the empty nanoparticle resulted in no changes in gait parameters; whereas, injection of solution-based VCR resulted in decreased run speed and increased step cycle and stance (P < 0.05). There were no differences in incidence and severity of degeneration in the sciatic nerves between the nano-VCR-dosed and solution-based VCR-dosed animals. Likewise, decreased levels of a nervous tissue-enriched microRNA-183 in circulating blood did not show a significant difference between the nano- and solution-based VCR groups (P > 0.05). Empty nanoparticle administration did not cause any behavioral, microRNA, or structural changes. In conclusion, this study suggests that the nano-VCR formulation may alleviate behavioral changes in CiPN, but it does not improve the structural changes of CiPN in peripheral nerve. Nanoparticle properties may need to be optimized to improve biological observations. [ABSTRACT FROM AUTHOR]

Chemotherapy-induced peripheral neuropathy (CiPN) is a serious adverse effect in the clinic, but nonclinical assessment methods in animal studies are limited to labor intensive behavioral tests or semi-quantitative microscopic evaluation. Hence, microRNA (miRNA) biomarkers and automated in-life behavioral tracking were assessed for their utility as non-invasive methods. To address the lack of diagnostic biomarkers, we explored miR-124, miR-183 and miR-338 in a CiPN model induced by paclitaxel, a well-known neurotoxic agent. In addition, conventional and Vium’s innovative Digital Vivarium technology-based in-life behavioral tests and postmortem microscopic examination of the dorsal root ganglion (DRG) and the sciatic nerve were performed. Terminal blood was collected on days 8 or 16, after 20 mg/kg paclitaxel was administered every other day for total of 4 or 7 doses, respectively, for plasma miRNA quantification by RT-qPCR. DRG and sciatic nerve samples were collected from mice sacrificed on day 16 for miRNA quantification. Among the three miRNAs analyzed, only miR-124 was statistically significantly increased (5 fold and 10 fold on day 8 and day 16, respectively). The increase in circulating miR-124 correlated with cold allodynia and axonal degeneration in both DRG and sciatic nerve. Automated home cage motion analysis revealed for the first time that nighttime motion was significantly decreased (P < 0.05) in paclitaxel-dosed animals. Although both increase in circulating miR-124 and decrease in nighttime motion are compelling, our results provide positive evidence warranting further testing using additional peripheral nerve toxicants and diverse experimental CiPN models. [ABSTRACT FROM AUTHOR]

Chemotherapy-induced peripheral neuropathy (CiPN) is a frequent adverse effect in patients and a leading safety consideration in oncology drug development. Although behavioral assessment and microscopic examination of the nerves and dorsal root ganglia can be incorporated into toxicity studies to assess CiPN risk, more sensitive and less labor-intensive endpoints are often lacking. In this study, rats and mice administered vincristine (75 μg kg−1 day−1, i.p., for 10 days in rats and 100 μg kg−1 day−1, i.p., for 11 days in mice, respectively) were employed as the CiPN models. Behavioral changes were assessed during the dosing phase. At necropsy, the sural or sciatic nerve was harvested from the rats and mice, respectively, and assessed for mechanical and histopathological endpoints. It was found that the maximal load and the load/extension ratio were significantly decreased in the nerves collected from the animals dosed with vincristine compared with the vehicle-treated animals ( P < 0.05). Additionally, the gait analysis revealed that the paw print areas were significantly increased in mice ( P < 0.01), but not in rats following vincristine administration. Light microscopic histopathology of the nerves and dorsal root ganglia were unaffected by vincristine administration. We concluded that ex vivo mechanical properties of the nerves is a sensitive endpoint, providing a new method to predict CiPN in rodent. Gait analysis may also be a useful tool in these pre-clinical animal models. [ABSTRACT FROM AUTHOR]

Context: Selective inhibitors of glycine transporter type 1 (GlyT1) increase synaptic glycine concentrations and are being developed to treat cognitive and negative symptoms of schizophrenia. However, increases in systemic glycine levels have been associated with visual disturbances and electroretinogram (ERG) alternations. Objective: To determine whether the selective GlyT1 inhibitor PF-03463275 causes changes in ERG responses in albino rats. Materials and methods: Male Sprague-Dawley rats were administered PF-03463275 subcutaneously at 1, 3 and 10 mg/kg 1 h prior to ERG acquisition. Scotopic and photopic luminance responses, photopic adaptometry and flicker responses were measured. Plasma and vitreous samples were obtained at necropsy for determination of PF-03463275 concentrations. Results: A dose-dependent reduction (up to ∼70%) in the amplitude of the scotopic ERG oscillatory potentials (OPs) was observed following PF-03463275 administration. The amplitude of the OPs was also negatively correlated to the concentration of PF-03463275 in the vitreous humor ( r = −0.64, p < 0.0001). With the exception of a small increase in scotopic ERG a-wave amplitude and latency no effects were observed on other ERG parameters tested. Conclusions: We conclude that inhibition of the GlyT1 transporter in the retina causes ERG changes which may underlie recent reports of visual disturbance with GlyT1 inhibitors in clinical trials. [ABSTRACT FROM AUTHOR]

Nerve growth factor (NGF) blocking therapies are an emerging and effective approach to pain management. However, concerns about the potential for adverse effects on the structure and function of the peripheral nervous system have slowed their development. Early studies using NGF antisera in adult rats reported effects on the size and number of neurons in the sympathetic chain ganglia. In the work described here, both young adult (6–8 week) and fully mature (7–8 month) rats were treated with muMab 911, a selective, murine, anti-NGF monoclonal antibody, to determine if systemic exposures to pharmacologically active levels of antibody for 1 month cause loss of neurons in the sympathetic superior cervical ganglia (SCG). State-of-the-art, unbiased stereology performed by two independent laboratories was used to determine the effects of muMab 911 on SCG neuronal number and size, as well as ganglion size. Following muMab 911 treatment, non-statistically significant trends toward smaller ganglia, and smaller and fewer neurons, were seen when routine, nonspecific stains were used in stereologic assessments. However, when noradrenergic neurons were identified using tyrosine hydroxylase (TH) immunoreactivity, trends toward fewer neurons observed with routine stains were not apparent. The only statistically significant effects detected were lower SCG weights in muMab 911-treated rats, and a smaller volume of TH immunoreactivity in neurons from younger rats treated with muMab 911. These results indicate that therapeutically relevant exposures to the anti-NGF monoclonal antibody muMab 911 for 1 month have no effect on neuron numbers within the SCG from young or old adult rats. [ABSTRACT FROM AUTHOR]

Though the portfolio of medicines that are extending and improving the lives of patients continues to grow, drug discovery and development remains a challenging business on its best day. Safety liabilities are a significant contributor to development attrition where the costliest liabilities to both drug developers and patients emerge in late development or post-marketing. Animal studies are an important and influential contributor to the current drug discovery and development paradigm intending to provide evidence that a novel drug candidate can be used safely and effectively in human volunteers and patients. However, translational gaps-such as toxicity in patients not predicted by animal studies-have prompted efforts to improve their effectiveness, especially in safety assessment. More holistic monitoring and "digitalization" of animal studies has the potential to enrich study outcomes leading to datasets that are more computationally accessible, translationally relevant, replicable, and technically efficient. Continuous monitoring of animal behavior and physiology enables longitudinal assessment of drug effects, detection of effects during the animal's sleep and wake cycles and the opportunity to detect health or welfare events earlier. Automated measures can also mitigate human biases and reduce subjectivity. Reinventing a conservative, standardized, and traditional paradigm like drug safety assessment requires the collaboration and contributions of a broad and multi-disciplinary stakeholder group. In this perspective, we review the current state of the field and discuss opportunities to improve current approaches by more fully leveraging the power of sensor technologies, artificial intelligence (AI), and animal behavior in a home cage environment., Competing Interests: BB is self-employed as a consultant to TLR Ventures. SB is employed by VeriSIM Life. NB-P and TR are employed by TLR Ventures. C-NL is employed by Pfizer. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Berridge, Baran, Kumar, Bratcher-Petersen, Ellis, Liu and Robertson.)

Introduction: Wistar Han rats are a preferred strain of rodents for general toxicology and safety pharmacology studies in drug development. In some of these studies, visual functional tests that assess for retinal toxicity are included as an additional endpoint. Although the influence of gender on human retinal function has been documented for more than 6 decades, preclinically it is still uncertain if there are differences in retinal function between naïve male and female Wistar Han rats. Methods: In this study, sex-related differences in the retinal function were quantified by analyzing electroretinography (ERG) in 7-9-week-old ( n = 52 males and 51 females) and 21-23-week-old Wistar Han rats ( n = 48 males and 51 females). Optokinetic tracking response, brainstem auditory evoked potential, ultrasonic vocalization and histology were tested and evaluated in a subset of animals to investigate the potential compensation mechanisms of spontaneous blindness. Results/Discussion: Absence of scotopic and photopic ERG responses was found in 13% of 7-9-week-old (7/52) and 19% of 21-23-week-old males (9/48), but none of female rats (0/51). The averaged amplitudes of rod- and cone-mediated ERG b -wave responses obtained from males were significantly smaller than the amplitudes of the same responses from age-matched females (-43% and -26%, respectively) at 7-9 weeks of age. There was no difference in the retinal and brain morphology, brainstem auditory responses, or ultrasonic vocalizations between the animals with normal and abnormal ERGs at 21-23 weeks of age. In summary, male Wistar Han rats had altered retinal responses, including a complete lack of responses to test flash stimuli (i.e., blindness), when compared with female rats at 7-9 and 21-23 weeks of age. Therefore, sex differences should be considered when using Wistar Han rats in toxicity and safety pharmacology studies with regards to data interpretation of retinal functional assessments., Competing Interests: All authors were employed by Pfizer at the time of the study., (Copyright © 2023 Tyszkiewicz, Hwang, Manickam, Jakubczak, Walters, Bolt, Santos and Liu.)

The potential for neurogenesis in the cranial (superior) cervical ganglia (SCG) of the sympathetic nervous system was evaluated. Eleven consecutive daily doses of guanethidine (100 mg/kg/d) were administered intraperitoneally to rats in order to destroy postganglionic sympathetic neurons in SCG. Following the last dose, animals were allowed to recover 1, 3, or 6 months. Right and left SCG from guanethidine-treated and age-matched, vehicle-treated control rats were harvested for histopathologic, morphometric, and stereologic evaluations. Both morphometric and stereologic evaluations confirmed neuron loss following guanethidine treatment. Morphometric analysis revealed a 50% to 60% lower number of tyrosine hydroxylase (TH)-positive neurons per unit area of SCG at both 3 and 6 months of recovery, compared to ganglia of age-matched controls, with no evidence of restoration of neuron density between 3 and 6 months. Reductions in TH-positive neurons following guanethidine treatment were corroborated by unbiased stereology of total hematoxylin and eosin-stained neuron numbers in SCG. Stereologic analyses revealed that total neuron counts were lower by 37% at 3 months of recovery when compared to age-matched vehicle controls, again with no obvious restoration between 3 and 6 months. Thus, no evidence was found that postganglionic neurons of the sympathetic nervous system in the adult rat have a neurogenic capacity.

This retracts the article entitled, "Effects of Sodium Lighting on Circadian Rhythms in Rats" by Xian Chen, Chang-Ning Liu, and Judith E Fenyk-Melody published in the May issue vol 58, issue 3, p 311-320. 1 This article is being retracted with the support of all 3 coauthors due to methodological and authorship issues.

Rodent studies often must be conducted during an animal's active phase (that is, in darkness) yet also during a typical day shift for staff. Low-pressure sodium lighting (LPSL), to which human retinas are more sensitive than rodents' at low intensity, has been used to facilitate study conduct in dark phase. The assumption was that LPSL would be equivalent to total darkness due to low rodent retinal sensitivity but provide enough lighting for safe technical manipulations due to higher human retinal sensitivity. Unlike other light sources, LPSL has been tested for effects on circadian rhythm specific to locomotive activities in albino mice. Whether LPSL affects circadian rhythms in rats is unknown. In this study, circadian endpoints were derived from body temperature and locomotor activity via telemeters in 8 adult male Wistar rats. When moved from a 12:12-h white-light (that is, cold white fluorescent light):dark (LD) cycle to a 12:12-h white-light:sodium-light cycle, rats demonstrated free-running and disrupted circadian rhythms (that is, lengthened circadian period and reduced circadian robustness and amplitude). Body temperature and locomotor activity were significantly lower in the LPSL phase as compared with dark phase under the baseline condition. When exposed to a 12:12 h sodium-light:dark (SD) cycle, rats entrained with a circadian period similar to 12:12-h white-light:dark (LD), but significantly different from the period under constant darkness (DD). Circadian onset and acrophase were delayed under SD compared with LD. When illuminated with a LPSL pulse under DD, rats showed phase shifts similar to white-light pulse effects, consistent with the phase response curve. To determine whether the image-forming photoreceptors are involved in this process, we used electroretinography. Compared with white light, 589-nm light generated during electroretinography elicited rod photoreceptors responses with longer latency and cone photoreceptor responses with lower amplitude. These results indicate that LPSL is a weaker zeitgeber than white light and may alter the circadian system in rats. Furthermore, because LPSL appeared to be visible to rats, it may not be an appropriate substitute for actual darkness.

Aim: To investigate the impact of postoperative antiviral treatment on tumor recurrence and survival of patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection-related primary hepatocellular carcinoma (HCC) after curative therapy., Methods: We performed a meta-analysis of randomized and non-randomized control trials from electronic search and manual search. The fixed effect model of Mantel-Haenszel method and the random effect model of Der Simonian and Laird method were used for homogeneous and heterogeneous studies, respectively. Seven HCV-related studies, three HBV-related studies and three studies on HBV or HCV-related HCC were identified., Results: A total of 1224 patients were included in this analysis. The estimated odds ratios (OR) for the 1-, 2-, 3- and 5-year recurrence were 0.54 [15.4% vs 24.1%, 95% confidence interval (CI): 0.32-0.89, P = 0.02], 0.42 (36.9% vs 58.0%, 95% CI: 0.19-0.90, P = 0.03), 0.37 (47.9% vs 63.8%, 95% CI: 0.19-0.71, P = 0.003), and 0.32 (66.7% vs 74.3%, 95% CI: 0.15-0.66, P = 0.002), respectively; and the OR for the 1-, 2-, 3-, 5- and 7-year mortality were 0.23 (1.2% vs 9.1%, 95% CI: 0.07-0.71, P = 0.01), 0.31 (6.4% vs 22.1%, 95% CI: 0.12-0.79, P = 0.01), 0.43 (12.7% vs 20.8%, 95% CI: 0.21-0.89, P = 0.02), 0.42 (25.1% vs 42.0%, 95% CI: 0.27-0.66, P = 0.0002) and 0.28 (31.9% vs 52.2%, 95% CI: 0.13-0.59, P = 0.0008)., Conclusion: This meta-analysis indicates the postoperative antiviral therapy, interferon in particular, may serve as a favorable alternative to reduce recurrence and mortality in patients with HBV/HCV related HCCs.

Whole cell patch-clamp recordings were obtained from dissociated mouse lumbar dorsal root ganglion (DRG) neurons. Recordings were made from control neurons and neurons axotomized by transection of the corresponding spinal nerve 1-2 days prior to dissociation. Medium to large muscle and cutaneous afferent neurons were identified by retrograde transport of True Blue or Fluoro-Gold injected into the corresponding peripheral tissue. Action potentials were classified as non-inflected spikes (A(0)) and inflected spikes (A(inf)). High-frequency, low-amplitude subthreshold membrane potential oscillations were observed in 8% of control A(0) neurons, but their incidence increased to 31% in the nerve injury group. Fifty percent of axotomized muscle afferent A(0) cells displayed oscillations, while 26% of axotomized cutaneous afferents exhibited oscillations. Lower-frequency oscillations were also observed in a small fraction (4%) of A(inf) neurons on strong depolarization. Their numbers were increased after the nerve injury, but the difference was not statistically significant. The oscillations often triggered burst firing in distinct patterns of action potential activity. These results indicate that injury-induced membrane oscillations of DRG neurons, previously observed in whole DRG of rats, are present in dissociated DRG neurons of the adult mouse. Moreover, these observations indicate that both muscle and cutaneous afferents in the A(beta) size range give rise to injury-induced membrane oscillations, with muscle afferents being more prone to develop oscillations.