This study applied a behavioral lens to understand drivers of COVID-19 vaccination uptake among healthcare workers (HCWs) in Nigeria. The study used data from an online survey of Nigerian HCWs ages 18 and older conducted in July 2021. Multivariate logistic regression analyses were conducted to examine predictors of getting two doses of a COVID-19 vaccine. One-third of HCWs in our sample reported that they had gotten two doses of a COVID-19 vaccine. Motivation and ability were powerful predictors of being fully vaccinated: HCWs with high motivation and high ability had a 15-times higher odds ratio of being fully vaccinated. However, only 27% of HCWs had high motivation and high ability. This was primarily because the ability to get vaccinated was quite low among HCWs: Only 32% of HCWs reported that it was very easy to get a COVID-19 vaccination. By comparison, motivation was relatively high: 69% of HCWs reported that a COVID-19 vaccine was very important for their health. Much of the recent literature coming out of Nigeria and other LMICs focuses on increasing motivation to get a COVID-19 vaccination. Our findings highlight the urgency of making it easier for HCWs to get COVID-19 vaccinations.

Insulin-like growth factor (IGF)-I is a ubiquitously synthesized peptide that, along with IGF-II, acts via the IGF-R type I receptor. IGF-I and its receptor are expressed in the adrenal gland of humans and bovines, the secretion of which they seem to stimulate. As in humans and cows, the main glucocorticoid hormone secreted by guinea-pig adrenals is cortisol, and hence we have studied the adrenocortical effects of IGF-I in this species. In vivo experiments showed that prolonged IGF-I administration raised the plasma concentration of cortisol in both normal and dexamethasone/captopriltreated guinea pigs, thereby ruling out the possibility that IGF-I may act by activating the hypothalamic-pituitaryadrenal axis and the renin-angiotensin system. In vitro experiments demonstrated that IGF-I enhanced basal, but not maximally agonist [ACTH and angiotensin-II (Ang-II)]stimulated, cortisol secretion from freshly dispersed guinea-pig inner adrenocortical cells. The IGF-I immuno-neutralization suppressed the IGF-I secretagogue effect, without altering the cortisol response to both ACTH and Ang-II. IGF-I raised cyclic-AMP and inositol triphosphate release from dispersed guinea-pig cells, and the effect was reversed by the adenylate cyclase inhibitor SQ-22536 and the phospholipase-C (PLC)

We have investigated the effect of the prolonged administration of melatonin on the plasma concentration of glucocorticoids in rats and palm squirrels, whose hypothalamo-pituitaryadrenal axis and renin-angiotensin system were suppressed by the simultaneous administration of dexamethasone and captopril. Dexamethasone and captopril administration for two weeks markedly lowered the blood level of corticosterone in rats and cortisol in palm squirrels. The injection of melatonin during the second week of treatment caused a further significant lowering in the glucocorticoid plasma concentration. These findings suggest that melatonin exerts a sizeable glucocorticoid antisecretagogue effect in rats and squirrels, acting directly on the adrenal glands.Melatonin is a multifunctional hormone, mainly secreted by the pineal gland, the effects of which on the hypothalamo-pituitary-adrenal (HPA) axis are well established (14). To summarize, melatonin is reported to be a potent inhibitor of the central branch of the HPA axis (16), as well as to reset dysregulation of this axis, at least in the rat (7). However, there is a marked disagreement as far as the direct effect of this hormone on the secretory activity of adrenal cortex is concerned. In fact, both stimulating (2, 4, 13, 15) and inhibitory effects have been described (5, 9, 11, 17). All these study were carried out using dispersed or cultured adrenocortical cells, i.e. experimental models which do not reproduce in viva physiolog- ical conditions. It, therefore, seemed worthwhile to study the effect of the prolonged melatonin administration on the blood concentrations of glucocorticoid in rats and palm squirrels, whose HPA axis and renin-angiotensin system (RAS) were pharmacologically interrupted.Adult Sprague-Dawley male rats (ZOO--250g body weight, obtained from Charles-River; Como, Italy), and palm squirrels (Fzmambzzlus pennanri, Wrougton) (300-350g body weight, obtained from the breeding facilities of our Zoology Department) were housed two per cage, kept under a 12:12 h light-dark cycle, and maintained on a standard diet and tap water ad Zibitrzzm. After being adapted to the laboratory conditions for 15 days, the animals were divided into three equal groups (rats: 11:10; palm squirrels: 11:50), which were treated as follows: 1) dexamethasone (2.5 mg/kg; Sigma Chemical Company, St. Louis, MO, U.S.A.) and captopril (8.3 mg/kg; Squibb, Rome, Italy) for 14 days; they were subcutaneously injected twice a day, at 1 a.m. and 1 p.m. to counteract circadian rhythm of glucocorticoids secretion which depends on both HPA axis and

Abstract. The effects of neuropeptide Y (NPY) on adrenal glucocorticoid secretion are controversial, and we have investigated this issue in guinea pigs, where, like in humans and cows, the main glucocorticoid hormone is cortisol. In vivo experiments showed that prolonged NPY administration markedly lowered cortisol plasma concentration not only in normal guinea pigs, but also in animals whose hypothalamicpituitary-adrenal axis and renin-angiotensin system had been pharmacologically interrupted by the simultaneous administration of dexamethasone and captopril. In vitro experiments ruled out the possibility that in vivo glucocorticoid anti-secretagogue action of NPY can ensue from a direct effect on the adrenal gland. In fact, NPY did not affect cortisol secretion from dispersed guinea pig inner adrenocortical cells. In contrast, NPY raised cortisol production from adrenal slices containing medullary tissue, and this effect was blocked by the ß-adrenoceptor antagonist l-alprenolol. This finding, coupled with the demonstration that NPY enhanced catecholamine release from guinea pig adrenomedullary tissue, strongly suggests that NPY may stimulate glucocorticoid secretion in this species through an indirect mechanism involving catecholamines, that in a paracrine manner promote the secretion of inner adrenocortical cells. In light of these observations, the conclusion is drawn that the in vivo effects of NPY are mediated by mechanism(s) independent of either the suppression of the main adrenal agonists ACTH and angiotensin-II or the direct inhibition of adrenal secretion. The possibility merits an investigation into whether NPY enhances the production of peptides, which, like leptin, inhibit adrenal glucocorticoid secretion acting as circulating hormones.

Technological advancements have trigged the research arena of life sciences. This has resulted not only in the co-evolution of science and technology but also in building up novel ways to tackle life threatening pandemic like situations. The use of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) technology in combating the recent COVID-19 pandemic is evidence to this. The technique was originally identified as a microbial adaptive immune system, in which the microbes use RNA-guided nucleases to cleave foreign genetic material. Subsequently, molecular biologists started harvesting this technique in accelerating the genetic engineering/ chimeric DNA methods. During COVID-19 outbreak, the scientists are trying to mould the CRISPR technology in the successful and rapid detection of the virus and also in the treatment of COVID- 19 infection. Thus the application of this technique comes as a ray of hope not only for fighting against COVID but also can be used as weapon for unseen future pandemics.