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Kawasaki disease (KD) is a form of acute systemic vasculitis syndrome that predominantly occurs in children under the age of 5 years. Its etiology has been postulated due to not only genetic factors but also the presence of foreign antigens or infectious agents. To evaluate possible associations between Kawasaki disease (KD) and COVID-19, we investigated humoral responses of KD patients against S-protein variants with SARS-CoV-2 variant protein microarrays. In this study, plasma from a cohort of KD (N = 90) and non-KD control (non-KD) (N = 69) subjects in categories of unvaccinated–uninfected (pre-pandemic), SARS-CoV-2 infected (10–100 days after infection), and 1-dose, 2-dose, and 3-dose BNT162b2 vaccinated (10–100 days after vaccination) was collected. The principal outcomes were non-KD–KD differences for each category in terms of anti-human/anti-His for binding antibodies and neutralizing percentage for surrogate neutralizing antibodies. Binding antibodies against spikes were lower in the KD subjects with 1-dose of BNT162b2, and mean differences were significant for the P.1 S-protein (non-KD–KD, 3401; 95% CI, 289.0 to 6512; P = 0.0252), B.1.617.2 S-protein (non-KD–KD, 4652; 95% CI, 215.8 to 9087; P = 0.0351) and B.1.617.3 S-protein (non-KD–KD, 4874; 95% CI, 31.41 to 9716; P = 0.0477). Neutralizing antibodies against spikes were higher in the KD subjects with 1-dose of BNT162b2, and mean percentage differences were significant for the 1-dose BNT162b2 B.1.617.3 S-protein (non-KD–KD, −22.89%; 95% CI, −45.08 to −0.6965; P = 0.0399), B.1.1.529 S-protein (non-KD–KD, −25.96%; 95% CI, −50.53 to −1.376; P = 0.0333), BA.2.12.1 S-protein (non-KD–KD, −27.83%; 95% CI, −52.55 to −3.115; P = 0.0195), BA.4 S-protein (non-KD–KD, −28.47%; 95% CI, −53.59 to −3.342; P = 0.0184), and BA.5 S-protein (non-KD–KD, −30.42%; 95% CI, −54.98 to −5.869; P = 0.0077). In conclusion, we have found that KD patients have a comparable immunization response to healthy individuals to SARS-CoV-2 infection and COVID-19 immunization. [ABSTRACT FROM AUTHOR]

Pregnant and ovariectomized rats were used to investigate the effects of ovarian steroid hormones and thyroxine on the secretion of calcitonin. Plasma progesterone, calcitonin secretion before and after calcium challenge and the time for calcitonin to return to baseline were monitored. These parameters were at their peak values at mid-pregnancy. Analysis of these results showed that mid-term hypercalcitonemia is brought about by increased levels of progesterone while hypocalcitonemia late in pregnancy is due to hypocalcemia.

The gastric emptying and gastrointestinal (GI) transit of nonnutrient liquid meal was measured in lactating, postweaning and nonpregnant rats in the diestrous stage to determine the effects of lactation on GI function. Analysis of GI function during postpartum in rats indicated the presence of enhanced gastric emptying which was attenuated by preweaning. Furthermore, geometric center and charcoal transit increased during the early stages of lactation and gradually returned to normal levels as lactation proceeded towards the weaning state.

The mechanism of lactate-induced increases in progesterone secretion in female rats after a brief period of intensive exercise was investigated in vitro and in vivo. In vitro experiments showed that lactate induces progesterone production in the ovarian tissue via stimulation of ovarian adenosine 3',5'-cyclic monophosphate. However, progesterone release is independent of plasma leutinizing hormone secretion.

The secretion of erythropoietin (EPO) and testosterone in response to hypoxia in old (22-25 months), middle (mid)-aged (15-17 months), adult (6-7 months), and young (3 months) male rats was studied. Rats of different ages were bled by cardiac puncture before and subsequent to 8 h exposure to 12% [0.sub.2]. The metabolic clearance rate of EPO was determined by a single-injection method. The effects of orchidectomy and replacement of testosterone propionate on plasma EPO concentrations were also investigated. Analysis of the direct effects of testosterone on EPO release from kidney tissue was carried out in an in vitro study. Both basal and hypoxia-induced EPO levels were lower in old rats than in mid-aged, adult, and young rats (p < .01). Plasma testosterone levels decreased in response to hypoxia in all rats (p < .01 for young, adult, and mid-aged rats, and p < .05 for old rats). The old rats also had lower plasma testosterone levels following hypoxia when compared with other rats (p < .05). The metabolic clearance rate of EPO was not affected by age. Orchidectomy decreased rat plasma EPO concentration (p < .05). This decrease could be restored to intact levels after testosterone propionate replacement. Both [10.sup.-10] M (p < .05) and [10.sup.-9] M (p < .01) testosterone stimulate EPO release from kidney tissue in vitro. Our findings indicate that the basal levels of plasma EPO and testosterone are decreased, and the hypoxia-induced EPO is also diminished with aging in male rats. These data suggest that the mechanism of tolerance to hypoxia and the endocrine function of the kidneys in male rats during the aging process are testosterone-dependent.

Background: The COVID-19 pandemic has led to millions of fatalities globally. Kidney transplant (KT) patients, given their comorbidities and under immunosuppressant drugs, are identified as a high-risk group. Though vaccination remains pivotal for pandemic control, some studies indicate that KT exhibits diminished immune reactions to SARS-CoV-2 vaccines. Therefore, evaluating the vaccine responses in KT, especially the humoral responses against emergent variants is crucial. Methods: We developed a multiplexed SARS-CoV-2 variant protein microarray, incorporating the extracellular domain (ECD) and the receptor binding domain (RBD) of the spike proteins from the variants. This was employed to investigate the collective humoral responses after administering two doses of mRNA-1273 and AZD1222 vaccines in KT under immunosuppressive drugs and in healthy controls. Results: After two doses of either mRNA-1273 or AZD1222, the KT generally showed lower surrogate neutralizing and total antibodies against spike ECD in multiple variants compared to healthy controls. Although two doses of mRNA-1273 induced 1.5-2 fold more surrogate neutralizing and total antibodies than AZD1222 in healthy controls, the KT subjects with two doses of mRNA-1273 generally exhibited higher surrogate neutralizing but similar total antibodies against spike ECD in multiple variants. There were moderate to high correlations between the surrogate neutralizing and total antibodies against spike ECDs. Conclusion: This study offers pivotal insights into the relative vulnerability of KT concerning humoral immunity and the evolving mutations of SARS-CoV-2. Such findings are useful for evaluating vaccine responses and recommending vaccine episodes for KT.