The visual field-testing maze and vision maze: Feasible techniques to evaluate visual field loss in animals

Visual field loss due to glaucoma is a severe and concerning problem, leading to limited visual range and poor quality vision. The progression of this loss begins with a para-central arcuate scotoma which eventually advances to a ring scotoma and constricted visual fields in later stages. Currently, no animal model is available for screening this pattern of vision loss. However, we have successfully developed two mazes to evaluate visual field loss - the visual field-testing maze (VFTZ) for peripheral vision loss and the vision maze (VM) for central vision loss. Our studies involved inducing glaucoma in Wistar and Sprague Dawley rats using lipopolysaccharide (LPS) and testing them in VFTZ and VM. We used Latanoprost and dorzolamide eye drops as standard drug candidates during the study. We evaluated the animals for intraocular pressure, retinal vasculature imaging, and anxiety using tonometry, ophthalmoscopy, and light and dark model techniques. Furthermore, we quantified the antioxidant parameters of the retina using UV spectroscopy. Our findings showed that animals with peripheral visual field loss in VFTZ took significantly more time to reach the goal and spent more time within the maze compared to normal or drug-treated animals (P < 0.001). Additionally, animals with compromised central visual field in VM spent more time in a particular arm and changed arms less frequently (P < 0.001) compared to normal or drug-treated animals. Moreover, we observed that glaucomatous rats exhibited elevated anxiety levels and impaired performance in the mazes, emphasizing the impact of vision loss on anxiety. Finally, the antioxidant and ATPase alterations in the retinal layers verified the glaucomatous changes in the experimental animals. Based on our remarkable findings, we strongly recommend the use of VFTZ and VM to evaluate visual field loss in animals.

Experimental investigations on PVA/chitosan and PVA/chitin films for active food packaging using Oxytenanthera abyssinica lignin nanoparticles and its UV-shielding, antimicrobial, and antiradical effects

This study investigated the effect of adding lignin nanoparticles (LNPs) derived from Oxytenanthera abyssinica via alkali-acid nanoprecipitation method to polyvinyl alcohol/chitosan (PVA/CI) and polyvinyl alcohol/chitin (PVA/CH) films for the active food packaging applications. Adding LNPs at concentrations of 1 % and 3 % improved the films' thermal stability and mechanical properties. The lowest water solubility and moisture content were observed in PVA/CI/LNPs films. LNPs exhibited effective 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities, with the highest values observed in PVA/CH/LNPS and PVA/CI/LNPS films with values of 87.47 and 88.74 % respectively. The addition of LNPs also improved the UV-blocking abilities of the films. PVA/CH/LNP3 and PVA/CI/LNP3 have the smallest percentage transmission values of 3.34 % and 0.86 % in the UV range. The overall migration of dietary stimulants was lower in PVA/CI/LNPS and PVA/CH/LNPS films compared to PVA film. Antibacterial tests demonstrated the inhibitory capacity of the synthesized biofilms against both gram-positive and negative bacterial species, with the highest inhibitory value of 26 mm. The study suggests that PVA/CH/LNPS and PVA/CI/LNPS films have potential applications as active food packaging materials and can be explored in other potential applications such as drug delivery, tissue engineering, wound healing, and slow-release urea fertilizer development.

Flavonoids and Phenolic Acids from Aerial Part of Ajuga integrifolia (Buch.-Ham. Ex D. Don): Anti-Shigellosis Activity and In Silico Molecular Docking Studies

Shigellosis is one of the major causes of death in children worldwide. Flavonoids and phenolic acids are expected to demonstrate anti-shigellosis activity and anti-diarrheal properties. The aerial part of A. integrifolia is commonly used against diarrhea. This study aimed to identify flavonoids and phenolic acids responsible for this therapeutic purpose. Antioxidant activity, total phenol content, and total flavonoid content were determined. The antibacterial activity of the aerial part against Shigella spp. was also tested using the agar well diffusion method. HPLC analysis was performed using UHPLC-DAD for different extracts of the aerial part. Autodock Vina in the PyRx platform was used to screen responsible components. Ciprofloxacin was used as a reference drug. An enzyme taking part in pyrimidine biosynthesis was used as a target protein. Molecular docking results were visualized using Discovery Studio and LigPlot1.4.5 software. Antioxidant activity, total phenol content, and total flavonoid content are more significant for the aerial part of A. integrifolia. From HPLC analysis, the presence of the flavonoids, quercetin, myricetin, and rutin and the phenolic acids gallic acid, chlorogenic acid, and syringic acid were identified from the aerial part of A. integrifolia. Regarding the antibacterial activity, the aerial part shows considerable activity against Shigella spp. Binding energies, RMSD and Ki values, interaction type, and distance are considered to identify the components most likely responsible for the therapeutic effects and observed activity. Antioxidant activity, total phenol content, and total flavonoid content of the aerial part are in line with anti-shigellosis activity. The top five components that are most likely potentially responsible for therapeutic purposes and anti-shigellosis activity are chlorogenic acid, rutin, dihydroquercetin, dihydromyricetin, and kaempferol.

Topical Administration of ACE Inhibitor Interrupts the Progression of Cataract in Two Kidney One Clip Induced Hypertensive Cataract Model

PURPOSE

Previously, we assessed that hypertension increases cataractogenesis. In the present study, we evaluated the effect of oral and topical administration of enalapril on two kidney one clip (2K1C)-induced hypertensive cataract model by evaluating the biochemical alteration of lenticular antioxidants, ionic content, ATPase activity, protein content and careful examination of the lenticular opacity.

MATERIALS AND METHOD

Animals were divided into normal and hypertensive animals. Hypertensive animals were divided into hypertensive control group (0.3% CMC), enalapril (oral) treatment group (20 mg/kg/day; p.o), and enalapril (topical) treatment group (0.1% w/v on the eye cornea) for a period of twelve weeks. During experimental study blood pressure, heart rate and morphology of the eyes were monitored biweekly. After twelve weeks, lenses were photographed and various catractogenic biochemical parameters were assessed.

RESULTS

Enalapril (oral) treatment conserved the blood pressure (systolic and diastolic), restored the level of antioxidants, restored the lipid peroxidation marker, nitrite content, ionic content, ATPase function, protein content, and thus delayed the cataract formation. While, enalapril (topical) treatment exhibited anti-cataract effect without affecting the systolic and diastolic blood pressure that could be by restoring the antioxidant level, maintaining the ionic balance, balancing the protein levels, and by inhibiting the upregulated ocular renin angiotensin system. The overall results suggest that enalapril (topical) treatment showed conspicuous effect than enalapril (oral) treatment in adjourning the cataract formation.

CONCLUSION

Based on the results, it may be concluded that upregulated ocular RAS by increasing oxidative stress and by misbalancing the lenticular ionic and protein content may lead to cataract formation in hypertensive condition.

Impact of first aid training in management of snake bite victims in Madi valley

BACKGROUND

Tropical lowland on Nepal is at full of risk to snake bite. The snake bite mortality is due to lack of awareness about proper management of victims. The study aims to assess the change in the pattern of management of snake bite victims after first aid training.

METHODS

A retrospective study was done from October 2007 to October 2008 among 43 snake bite victims in rural Madi valley comprising of 4 village development committees where first aid training was conducted one year before.

RESULTS

Only 26% of the snake bite victims approached traditional healer before arriving at the heath facility. The case fatality rate dropped to 22% after venomous snake bite. Pressure Immobilization bandaging and local compression pad immobilization technique was used by 56% who went to the health facility. Mean duration for reaching health facility was 61.51±33.55 minutes. Common places of bite were field 16 (37.2%), Indoor 6 (14%), while sleeping 6 (14%), and yard 6 (14%). Lower extremity bites were 32 (74.4%), upper extremity 8 (18.6%) and head 3 (7%). Bicycle was the commonest mode of transport 22 (51%) followed by ambulance 9(27.9%) and Motorcycle 6 (11%).

CONCLUSIONS

First aid training changes the attitude of the people in management of snake bite victims and is one of the effective ways in decreasing mortality. Nationwide campaigning should be done especially at snake bite prone area about the proper first aid technique to improve the awareness level of the general population.