CoronaVac was the first vaccine approved in Brazil for use in healthcare workers (HCWs). However, there is limited information about it, with little long-term evidence on post-vaccination antibody persistence. This study evaluated the antibody response to SARS-CoV-2 in 1237 HCWs after the first (1D), second dose (2D), and 6 months postvaccination (6mA2D) with CoronaVac. The seropositivity was 88% at 1D, increasing to 99.8% at 2D, but decreasing to 97.9% at 6mA2D, which was also observed at the analyzed antibody levels. Interestingly, the levels in females were higher than males, and we found a positive correlation with previous SARS-CoV-2 infection. Participants with comorbidities had lower levels suggesting the need to monitor for a potential booster dose. Our findings suggest that CoronaVac induced a robust antibody response that wanes significantly over time. Further longitudinal studies are needed to identify whether the antibodies will decline or plateau at a lower level.

Wound healing involves the interaction of blood cells, proteins, proteases, growth factors, and extracellular matrix components. Inflammation is one of the first events occurring during this process. Previously, we showed that the N-Methyl-(2S,4R)-trans-4-Hydroxy-L-Proline (NMP) from Sideroxylon obtusifolium leaves (a Brazilian medicinal species) presents an anti-inflammatory action. Considering inflammation as an important event in the wound healing process, the objectives were to investigate the topical effects of the NMP gel on a mice wound-induced model. Male Swiss mice were divided into 4 groups: Sham (surgical procedure only), Control (gel-base treated), and 3% or 10% NMP gel-treated groups. Measurements of wound areas and microscopic analyses (HE [hematoxylin-eosin] and PSR [picrosirius red] stainings) were carried out, at the 7th and 12th, days after the wound induction. Furthermore, immunohistochemical assays for iNOS (inducible nitric oxide synthase) and COX-2 (cyclooxygenase-2) and biochemical measurements for TBARS (thiobarbituric acid reactive substances), GSH (glutathione), and myeloperoxidase (MPO) were also performed, at the second day after the wound induction. The work showed that NMP decreases the wound areas, after topical application, relatively to the Sham and Control groups. In addition, microscopic alterations were reduced and collagen deposition was increased, at the 7th and 12th days, in the 10% NMP group. While iNOS and COX-2 immunostainings and GSH contents increased, in relation to the Sham and Control groups, TBARS and MPO decreased. Altogether, the results showed NMP to improve the wound healing process, by upregulating iNOS and COX-2 activities, reducing lipid peroxidation and MPO activity, and increasing GSH contents. In addition, NMP certainly contributes to the increased collagen deposition. These data may stimulate translational studies dealing with the possible use of NMP from Sideroxylon obtusifolium or from other sources for the management of wound healing.

The healing performance of a hydrogel composed of hemicelluloses extracted from seeds of Caesalpinia pulcherrima (Fabaceae) and mixed with phytomodulatory proteins obtained from the latex of Calotropis procera was characterized on excisional wounds. The hydrogel did not induce dermal irritability. When topically used on excisional wounds, the hydrogel enhanced healing by wound contraction. Histology and the measurement of inflammatory mediators (myeloperoxidase, interleukin-1β, and interleukin-6) suggested that the inflammatory phase of the healing process was intensified, stimulating fibroplasia and neovascularization (proliferative phase) and tissue remodeling by increasing new collagen fiber deposition. In addition, reduction on levels of malondialdehyde in the groups that the hydrogel was applied suggested that the oxidative stress was reduced. The hydrogel performed better than the reference drug used, as revealed by the extended thickness of the remodeled epithelium.

This work aimed to evaluate the activity of a lipid transfer protein isolated from Morinda citrifolia L. seeds, McLTP 1 , on the development of intestinal mucositis following irinotecan administration. McLTP 1 (0.5, 2 and 8 mg/kg, i.v.) was injected into mice 1h before irinotecan administration (75 mg/kg, i.p.; 4 days), and then for additional 6 days. Seven days after the rst dose of irinotecan, diarrhea was assessed and the intestine was removed for histological evaluation, assessment of intestinal over-contractility, measurement of myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA), proin ammatory cytokines and chemokine (IL-1, IL-6, and KC levels -a murine homolog of human IL-8 chemokine), analysis of cyclooxygenase 2 (COX-2), nuclear factor kappa B (NF-κB) and nitric oxide synthase (iNOS) expression. At the two highest doses, McLTP 1 administration decreased mortality and diarrhea. McLTP 1 (8 mg/kg, i.v.) signi cantly prevented irinotecan-induced intestinal damage and led to a reduction in overcontractility of the intestinal muscle (p < 0.05). Moreover, McLTP 1 decreased the MPO, IL-1β, IL-6, and KC levels signi cantly by 74.7%, 42%, 92.9%, and 95.9%, respectively. Also, the expression of COX-2, NF-κB, and iNOS was reduced. Pretreatment with McLTP 1 (8mg/kg; i.v.) signi cantly reduced the MDA level and increased the duodenum homogenates' GSH level. Our study provides a potential new therapeutic for preventing irinotecan-induced mucositis, improved clinical parameters, reduced in ammation, and oxidative damage.

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The larger number of plants, with therapeutic potential, popularly used in Northeastern Brazil is due to their easy access and the great Brazilian biodiversity. Previously, was demonstrated that the methanol fraction from Sideroxylon obtusifolium (MFSOL) promoted an anti-inflammatory and healing activity in excisional wounds. Thus, this work aimed to investigate the healing effects of MFSOL on human keratinocytes cells (HaCaT) and experimental burn model injuries. HaCaT cells were used to investigate migration and proliferation of cell rates. Female Swiss mice were subjected to seconddegree superficial burn protocol and divided into four treatment groups: Vehicle (cream-base), 1.0% Silver Sulfadiazine (Sulfa), and 0.5% or 1.0% MFSOL cream (CrMFSOL). Samples were collected for quantification of the inflammatory mediators and histological analyses after 3, 7 and 14 days on evaluation. As result, MFSOL (50 μg/ml) stimulated HaCaT cells by increasing proliferation and migration rates.Moreover, CrMFSOL 0.5% attenuated myeloperoxidase (MPO) activity and also stimulated the release of IL-1β and IL-10, after 3 days with treatment. CrMFSOL 0.5% enhanced wound contraction, promoted tissue remodeling improvement and highest collagen production after 7 days, and VEGF release after 14 days. Therefore, MFSOL evidenced the stimulation of human keratinocyte (HaCaT) cells and improvements on wound healing via inflammatory modulation on burn injuries.

It was previously demonstrated that the methanol fraction of Sideroxylon obtusifolium (MFSOL) promoted anti-inflammatory and healing activity in excisional wounds. Thus, the present work investigated the healing effects of MFSOL on human keratinocyte cells (HaCaT) and experimental burn model injuries. HaCaT cells were used to study MFSOL's effect on cell migration and proliferation rates. Female Swiss mice were subjected to a second-degree superficial burn protocol and divided into four treatment groups: Vehicle, 1.0% silver sulfadiazine, and 0.5 or 1.0% MFSOL Cream (CrMFSOL). Samples were collected to quantify the inflammatory mediators, and histological analyses were performed after 3, 7, and 14 days. The results showed that MFSOL (50 μg/mL) stimulated HaCaT cells by increasing proliferation and migration rates. Moreover, 0.5% CrMFSOL attenuated myeloperoxidase (MPO) activity and also stimulated the release of interleukin (IL)-1β and IL-10 after 3 days of treatment. CrMFSOL (0.5%) also enhanced wound contraction, promoted improvement of tissue remodeling, and increased collagen production after 7 days and VEGF release after 14 days. Therefore, MFSOL stimulated human keratinocyte (HaCaT) cells and improved wound healing via modulation of inflammatory mediators of burn injuries.

Plumeria rubra (Apocynaceae) is frequently used in folk medicine for the treatment of gastrointestinal disorders, hepatitis, and tracheitis, among other infirmities. The aim of this study was to investigate the gastroprotective potential of a protein fraction isolated from the latex of Plumeria rubra (PrLP) against ethanol-induced gastric lesions and describe the underlying mechanisms. In a dose-dependent manner, the pretreatment with PrLP prevented ethanol-induced gastric lesions in mice after single intravenous administration. The gastroprotective mechanism of PrLP was associated with the involvement of prostaglandins and balance of oxidant/antioxidant factors. Secondarily, the NO/cGMP/KATP pathway and activation of capsaicin-sensitive primary afferents were also demonstrated as part of the mechanism. This study shows that proteins extracted from the latex of P. rubra prevent gastric lesions induced in experimental animals. Also, the results support the use of the plant in folk medicine.