The pandemic of novel corona virus disease (covid 19), is presently sweeping the world over. The causative virus is named, SARS-CoV-2. The rapidity with which the pandemic is advancing is catastrophic. That there is no known treatment for this killer disease is throwing public at large into a state of fear psychosis. The urgent need for preventive vaccine is felt now, more than ever before Though promising research is going on, the goal to achieve a breakthrough vaccine is still a long way to go. Since SARS-CoV-2 is an infection restricted to respiratory system of the affected, vaccines aimed at inducing local (mucosal) immunity may offer better chance of preventing the acquisition and spread of the disease to others, than induction of systemic immunity. With this background theme, this article briefly reviewed the epidemiology, the vaccine trials of the Covid 19 as well as the immune responses to viral infection in general and with a special focus on the concept of Local immunity advanced by Prof Besredka (1924). The historical perspective of the local immunity concept is recapitulated and the diseases, both viral and bacterial, to which vaccines are developed in the past basing on this concept are reviewed. A case is made out for applying this concept for the prevention of covid 19. It is suggested that an approach to boost local immunity, than systemic immunity, might be a better strategy of prevention of covid 19.
This study was aimed at inducing immunity against Plasmodium berghei infection using cysteine protease in mice. Twenty laboratory mice were used for the study, they were grouped into 4 groups of 5 mice each. The first and second groups were immunized with 100 µg/l and 50 µg/l of purified cysteine protease respectively; the third group was administered with adjuvant which served as positive control while the fourth group (negative control) was not administered. All the groups were challenged with the parasite Plasmodium berghei. Results for percentage parasitaemia, Packed Cell Volume, Total Protein and Enzyme assay was recorded. Findings revealed that the mice immunized with the higher concentration of the cysteine protease had the lowest load of infection. The mice that were not immunized had the highest load of infection which showed that the cysteine protease conferred protection against infection.
Seizure is one of the neurological and episodic clinical challenges and, one underutilized option for medication-resistant in seizure is the use of medicinal plants. Dennettia tripetala has been found to possess anti-seizure effects. This study estimates the hematological parameters and examines the histopathological effect of ethanolic extract of Dennettia tripetala fruit on Isonaizid-induced seizure on the temporal lobe. Twenty-four (24) adult Wistar rats were randomized into six groups (1-6) of four rats each (n=4). The positive and negative control groups (group 1 and 2) received Isoniazid 300 mg/kg, i.p (inducing agent) and 1 ml, i.p normal saline (vehicle); while the rats in groups 3, 4, 5 and 6 were induced with 300 mg/kg of Isoniazid and treated with 250 mg/kg, 500 mg/kg and 750 mg/kg of the extract and 50 mg/kg of sodium valproate, o.p respectively. In the hematological study, the blood parameters RBC, PCV and HB decreased, while WBC remained normal and decrease eosinophils count was noted. Histopathological changes observed in the untreated seizure induced (positive control) group presented atrophied neurons, shrunken neurons, coagulative necrosis and microcystic spaces. The extract treated groups exhibited dose dependent reduction in the above histopathological features as well as the sodium valproate standard drug group. This implies that, Dennettia tripettala fruit extract at high dose exerts hematotoxic effect, while neuroprotective effect was observed at low dose. In conclusion, it is safe and effective at low dosage.
Background: The use of household insecticides for the eradication of insects especially mosquitoes in Nigeria is increasing. These insecticides are used without consideration of their adverse effect on human health.
Aim: This study is therefore sought to investigate the effect of common household insecticides used in Nigeria on oxidative stress biomarkers.
Methodology: Thirty (30) male Wistar rats were divided into five groups of six (6) each. Rats in group 1 were exposed to Rambo, those in group 2 were exposed to Mortein, those in group 3 were exposed to Raid, those in group 4 were exposed to Baygon while those in group 5 were not exposed to any insecticide and served as the control group. The exposure was done twice daily via inhalation route. Throughout the experiment, animals were fed ad libitum with standard feed and drinking water. After twenty-one (21) days of exposure, they were sacrificed after an overnight fast under diethyl ether as anesthesia. Blood samples were collected via cardiac puncture. Oxidative stress biomarkers (lipid peroxidation, glutathione, catalase, superoxide dismutase and glutathione peroxidase) were determined using standard methods.
Results: The results obtained showed that exposure of the animals to all types of insecticides (Rambo, Mortein, Raid and Baygon) significantly (p <0.05) increased lipid peroxidation an index of oxidative biomarkers in rats when compared to the control group. Conversely, the concentration of glutathione was significantly (p <0.05) reduced compared to the corresponding control group.While the activities of antioxidant enzymes (catalase, superoxide dismutase and glutathione peroxidase) were observed to significantly (p < 0.05) increase as a result of insecticides exposure to animals when compared with the control group animals.
Conclusion: From the findings of the present study, it can be concluded that common household insecticides used in Nigeria induced oxidative stress in Wistar rats and might compromise the immune system. Suggesting that such oxidative stress inducing effects of these insecticides as observed in animals used in this study may be extrapolated in humans who use these insecticides to protect against various insects. Therefore, staying in a room fumigated with these insecticides when the effect has not completely subsided may be hazardous to humans and hence, this should be discouraged.
In recent years, research has focused on natural mechanisms for the management, treatment, and curing of human infections and diseases. One of such natural methods is the application of probiotics, which are live microorganisms which when administered in adequate amounts confer a health benefit on the host. The beneficial effects associated with probiotics were originally thought to be a result of improvements in the intestinal microbial balance, however, there are shred evidence that probiotics can also provide benefits by modulating the immune functions. The ability of these probiotics, majorly the Lactobacillus and Bifidobacterium species to boost the immune system is proposed to be a result of their interactions with the cells of the immune system. They have been reported to stimulate various parts of the immune system, through several mechanisms enhancing their functions. It has also been established that the effects of probiotic bacteria may also result from soluble factors from these microbes that alter epithelial permeability or mediate activation, maturation or survival of dendritic cells, B and T-cells. Probiotic bacteria, their cell wall components, and other stimulating molecules have been shown to have significant effects on the functionality of the immune systems through the activation of multiple immune mechanisms. This study is aimed at describing the immunological mechanisms of probiotics and their beneficial effects on the host immune system.