Abstract

Grapefruit seed extract (GSE), which contains flavonoids, possesses antibacterial, antiviral, and antifungal properties. This study investigated the antimicrobial activity of cellulose-bound GSE microfibers against mouse hepatitis virus (MHV) for three weeks and against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa for one week. The disinfectant was smeared on a petri dish to inactivate the MHV for three weeks or to prevent the growth of the selected bacteria for one week. As the disinfectant effect lasted at least one week, GSE microfibers could have applications in disinfecting laboratory animal facilities. The virus or bacteria mixed with the disinfectant did not cause cytopathic effects in the cells or growth on the media after one week.

Abstract

Animal models of hypertension are crucial for studying the pathophysiology of diseases and developing new treatments. This study introduces a reproducible technique for inducing surgical renovascular hypertension in rats using a smaller renal artery clip. The surgical groups were compared to the control group and standard drug group to assess the effectiveness of the surgical model and its stability for 21 days. The results revealed a progressive increase in systolic and diastolic blood pressure in the surgical group. Moreover, the heart rate and body weight in the renal hypertension group demonstrated a sustained elevation at the end of 21 days. These findings confirm the efficacy of this surgical model in inducing hypertension. This surgical animal model is helpful for studying physiological parameters for investigating potential therapeutic interventions against hypertensi

Abstract

However, little evidence has been documented to evaluate the clear specific effects of neem-active ingredients in a rat model. This study aims to evaluate the in vitro effects of nimbolide (tetranortriterpenoids group, one of the main components of neem leaves), particularly on sperm functional studies, and biochemical and molecular events during capacitation in a dose-dependent manner. The results showed a dose- and time-dependent decrease in the functional consequence of capacitation process i.e., motility score, percentage of motile spermatozoa, Sperm Motility Index (SMI) and levels of molecular events in sperm followed by declined spontaneous acrosome reaction (AR), which subsequently leads to lesser binding of cauda epididymal sperm to the Zona pellucida (ZP). Biochemical studies have shown that the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase, Glutathione reductase (GR) and Glutathione peroxidase (GPx) decreased significantly while the levels of Hydrogen peroxide (H2O2) generation and lipid peroxidation (LPO) increased significantly in the treated groups indicating nimbolide-induced oxidative stress in rat epididymal sperm. This study confirmed that nimbolide convincingly inhibited sperm motility in rats by blocking certain biochemical pathways, such as energy utilization, and showed that sperm capacitation was associated with a reduction in AR, with changes in antioxidant enzymes reflecting a reduction at the levels of molecular events. This will lead us to produce a special product as a source of a new male contraceptive.

Abstract

Anesthesia is an important procedure performed in laboratory animals as part of the experimental activity. A calibrated vaporizer is recommended for precision delivery and efficient scavenging is an integral part of avoiding possible health hazards for personnel involved in gas anesthesia. The vivarium facility is equipped with scavenging devices such as activated charcoal canisters, spot extractors, fume hoods, and biosafety cabinets those are engineering controls used during isoflurane anesthesia. A modified prototype was necessitated especially when rodent procedures were conducted on the table due to a higher turnover in a barrier-maintained facility. Hence, a well-designed prototype with different shapes was developed to improve the scavenging methods during long-term tabletop anesthesia procedures where numerous animals are handled to complete the activities within the timeframe. The concentration of waste anesthetic gas was captured systematically from 13 laboratory personnel at different intervals and analyzed for quantitative exposure assessment for isoflurane. The results revealed that the waste anesthetic concentration captured for laboratory personnel was between 0.08 to 1.45 ppm. This result is below the reported recommended laboratory concentration (0.23 - 3.40 ppm). Moreover, the Time Weighted Average (TWA) personal exposure to isoflurane was found to be below the Health and Safety Executive (HSE) established Workplace Exposure Limit (WEL)-TWA (8 hours) of 50 ppm. The National Institute for Occupational Safety and Health (NIOSH) has a non-regulatory recommended exposure limit (REL) for halogenated agents (e.g., isoflurane) of 2 ppm or 15 mg/m3 as a ceiling limit (over a sampling period not to exceed one hour) during anesthetic administration. The Occupational Safety and Health Administration (OSHA) has not established a regulatory permissible exposure limit (PEL) for anesthetic gases; therefore, 2 ppm is used as the exposure threshold. Since each laboratory research and environmental conditions vary, it is important that exposure monitoring is performed at least one time to ensure isoflurane levels are less than 2 ppm. Overall, the implementation of a newly developed prototype along with canisters and an intensive exposure assessment was found to efficiently capture the waste anesthetic gas from induction chambers and surgical areas with nose-cone where isoflurane is constantly delivered during anesthesia. The portable setup with active suction arms and flexible hose connectors can be placed on a table and/or enclosure to reduce the occupational exposure of Isoflurane to laboratory personnel and demonstrated that the prototype had improved the scavenging practices in the vivarium.

Abstract

Animal models are important in biomedical research for validation of in vitro results, conducting proof of concept studies, and investigating the variety of disease processes and therapeutic targets that help in narrowing the gap between bench and bedside. The advent of precise genome engineering technologies has allowed the generation of an increasing number of novel and complex genetically engineered mouse models that can be made available to the scientific and research community. It is important to also provide access to efficient technologies to safely archive, protect, manage, and maintain these precious mouse models. Assisted Reproductive Technologies (ARTs) are emerging as an important tool in the strategic management of vivariums, which involves animal welfare, disaster preparedness, cost minimization, and most importantly, reproducible research.
To disseminate high-end skills of ARTs in laboratory mouse models, the MGEF team conducted a hands-on workshop on "Cryobiology and Assisted Reproductive Technologies in the Laboratory Mouse" held at the National Centre for Biological Sciences and Institute for Stem Cell Science and Regenerative Medicine from September 11th to September 14th, 2023. 20 professionals from all over India were selected and trained in this workshop by our highly expert staff. The workshop was designed to provide an in-depth understanding and practical knowledge in the field of ARTs and repository management in laboratory animals.