Lead is among the chemical compounds that have been reported to cause devastating problem worldwide. The primary site of action of lead is the central nervous system. This study investigated some effects of lead acetate on the cerebral cortex of adult Wistar rats. Thirty six adult Wistarrat of both sexes weighing between 120 g-250 g were randomly grouped into four groups of nine animals per group. Group A rats which was the control was maintained on standard feed and distilled water for 28 days, group B rats were treated with 10 mg/kg of lead acetate for 28 days, group C rats were treated with 20 mg/kg of lead acetate for 28 days and group D rats were also treated with 40 mg/kg of lead for 28 days. The lead acetate solution was administered orally on daily basis. The weights of the Wistar rats was recorded on weekly basis using a sensitive balance (before and during the weeks of administration). On the 28th day of the treatment the Wistar rats in group A, B, C and D were sacrificed by cervical dislocation, the brain was removed and weighed immediately using a sensitive balance, part of the brain was collected and homogenized for biochemical analysis for MDA.GSH and NO, the remaining part was then fixed in 10% formol calcium, the tissue was processed and sectioned at 5μm and stained with Haematoxylin and Eosin for histological study. The morphometric result showed that the mean body weights of the Wistar rats reduced significantly (P<0.05) in group B,C and D which received 10 mg/kg, 20 mg/kg and 40 mg/kg of lead acetate respectively as compared with Group A which reduced insignificantly (P>0.05). The brain weights in group B, C and D also decreased insignificantly (P>0.05) when compared with group A (control group). In the biochemical analysis there was statistically significant increase (p<0.05) in the level of Malondialdehyde (MDA) and Nitric Acid (NO) and statistically decreased level of Glutathione (GSH) in group B, C and D as compared with group A. Histological study of the cerebral cortex revealed that the cerebral cortical layers in group B, C and D appeared distorted and degenerated and in a dose dependent manner as compared with group A which shows a normal cerebral cortical architecture. This study concluded that lead has a neurotoxic effect on the cerebral cortex of adult Wistar rats which may adversely affect some cerebral functions

Objective: The COVID-19 pandemic has highlighted the importance of health care professionals; therefore, the education of future Doctors is highly relevant. This year, as medical student lectures have been delivered via online platforms like Zoom, it is important to explore attitudes towards Zoom lectures, to establish their impact on student welfare and education. The attitudes were of 1st year medical students. The hypotheses were: medical students would be negative towards Zoom online lectures; the age of the student would impact the perception of Zoom online lectures; and females would be more positive towards Zoom online lectures compared to males.

Methods: 20 randomized statements regarding Zoom online lectures were devised (ten positive and ten negative) and then scored according to the Thurstone and Chave method. An online survey was designed in Google Forms and, following ethical approval, distributed amongst 1st year medical students. Responses from 52.5% of Cardiff University 1st year medical students were received, and mean scores were calculated. The Wilcoxon test evaluated significant differences between groups.

Results: Medical students had an overall positive attitude towards Zoom online lectures. There was no significant difference by gender (p=0.8826 W=3257.5). 20+ year old students had the most positive perception which was significantly more positive than 18 (p=0.0002501 W=1625.5) and 19-year-olds (p=0.009936 W=1476.5).

Conclusion: 1^st year medical students showed a positive perception towards online Zoom online lectures. Gender had no effect; however, age played a significant role, with those aged 20+ having a more positive perception than 18- and 19-year-olds.

Objective: The importance of understanding the effectiveness of online teaching was highlighted by the COVID-19 pandemic, with students more commonly studying remotely, specifically, via Zoom. However, attitudes of science students to online lectures are largely unknown; consequently, understanding attitudes will help develop the most effective ways to deliver lectures, taking into consideration student well-being.

The hypotheses were: science students would have a negative perception towards Zoom online lectures; biomedical students would be more negative towards Zoom online lectures than other science students.

Materials and methods: To evaluate perceptions of Zoom online lectures, 20 statements were developed utilising the Thurstone and Chave method 1951. Using these statements, an online questionnaire was made, utilising Google Forms. With ethical approval, the questionnaire was sent out to undergraduate bioscience students via university email addresses. Survey responses were collated; based on agreement to the scored statements, mean scores were calculated. The Wilcoxon test was used to identify any significant statistical differences.

Results: The mean score for all science students indicated positive perception, with no significant difference between Biomedical science students and other science degrees, such as between Biomedical science and Biochemistry (p=0.3374 U=3527). Males had a more positive perception than females (p=0.02207 W=13946). Between ages 18-19 years and those aged 20+ there was no significant difference (p=0.1719 W=17586).

Conclusion: Overall, the perception of science students to Zoom online lectures was positive. There were no significant differences between different degrees: Biomedical science students were not more positive. Significant difference between genders was seen, however, age had no impact.

Mercury is sliver in colour, toxic metallic chemical element that is liquid at room temperature known to be a widespread environmental and industrial pollutant which induced several alternations in the tissues, and produces peripheral neuropathy in experimental animals and human beings. It finds its application in cosmetics manufacturing companies, dental filling, stabilizing agent. The present study investigated the possible adverse effect of mercury chloride on the liver of adult wistar rats. Thirty six adult wistar rates of both sexes weighing between 110 g-300 g were randomly grouped into four groups; group A,B,C,D with each group containing 9 rats and group. A served as the control group maintained daily with feed and water. The other groups B, C and D were given mercury chloride solution orally containing 0.2 g/kg, 0.4 g/kg and 0.5 g/kg body weight of mercury chloride respectively alongside the fed and water for 21 days and weighed weekly after which they were sacrificed using cervical dislocation. Blood was obtained through cardiac puncture for assay of hepatic markers; Alkaline Phosphatase (ALP), Asparatate Transaminase (AST) and Alanine Transaminase (ALT). then liver was removed, weighed and fixed in 10% formol saline and processed for histological studies using Haemotoxylin and Eosin (H and E) staining technique.

Results obtained show as significant (P<0.05) decrease in body weights of the treated groups B, C and D as compared with the control group A. There was no significant (P>0.05) decrease in organ weights of the wistar rats. Histological observation revealed well preserved histo-architecture in the control group A. however treated group B, C and D showed inflammation of cells, enlargement of the central vein, distorted sinusoids and hemorrhage around the central vein. Biochemical analysis for ALP showed a significant increase in the treated group B, C and D but statistically significant (P<0.05) in group C and D only as compared to control group A, AST showed a significant increase in all treated group A, C, and D and all showed statistically significant values (P<0.05) as compared to control group A and ALT showed a significant increase in all treated group B, C and D and all showed statistically significant values (P<0.05) as compared to control group A. The study then concluded that mercury chloride exposure induced hepatic damage with elevated haptic enzymes, this may ultimately impair hepatic functions in wistar rats.