ABSTRACT
Abstract Human milk constitutes a secretion with unique functions of both nourishing the nursling and providing protection against enteric and respiratory infections, mainly due to its content of secretory IgA antibodies but also due to the presence of a plethora of bioactive factors. Specific IgA antibodies are produced locally by plasma cells derived from B lymphocytes that migrate from other mucosae to the mammary gland during lactation, particularly from the gastrointestinal and respiratory tracts. Therefore, here, the authors will provide a comprehensive review of the content and functions of different nutritional and bioactive anti-infectious components from breast milk, such as oligosaccharides, lactoferrin, haptocorrin, α-lactalbumin, k-casein, lysozyme, lactoperoxidase, mucin, fatty acids, defensins, cytokines and chemokines, hormones and growth factors, complement proteins, leukocytes and nucleic acids, including microRNAs, among many others, and the induction of antibody responses in breast milk after maternal vaccination with several licensed vaccines, including the anti-SARS-CoV-2 vaccine preparations used worldwide. Currently, in the midst of the pandemic, maternal vaccination has re-emerged as a crucial source of passive immunity to the neonate through the placenta and breastfeeding, considering that maternal vaccination can induce specific antibodies if performed during pregnancy and after delivery. There have been some reports in the literature about milk IgA antibodies induced by bacterial antigens or inactivated virus vaccines, such as anti-diphtheria-tetanus-pertussis, anti-influenza viruses, anti-pneumococcal and meningococcal polysaccharide preparations. Regarding anti-SARS-CoV-2 vaccines, most studies demonstrate elevated levels of specific IgA and IgG antibodies in milk with virus-neutralizing ability after maternal vaccination, which represents an additional approach to improve the protection of the nursling during the entire breastfeeding period.
ABSTRACT
Millions of children live in Brazil’s semi-arid region, one of the most socially-deprived areas of the country, where undernutrition co-exists with obesity as a consequence of the nutrition transition. There is evidence that childhood obesity predisposes adult obesity and, thus, that obesity should be prevented as early as possible. Some studies have shown that breastfeeding is a protective factor against overweight and obesity while other studies have not found this association. There have been few studies on this association in developing countries and of children below two years of age. The present study aimed to investigate whether children exposed to exclusive breastfeeding for ≥6 months showed a lower prevalence of overweight in the second year of life, based on a probability sample of 2,209 children (aged 12 to 24 months). The dependent variable was overweight, defined as weight-for-length z-scores of >2, based on the WHO 2006 standard while the independent variable was exclusive breastfeeding (≥6 months). The prevalence ratio (PR) and its 95% CI were estimated using Poisson regression with robust adjustment of variance. After adjusting for potential confounding factors (socioeconomic, demographic and health-related variables), children on exclusive breastfeeding for ≥6 months showed a lower prevalence of overweight (5.7% vs 9.1%, PR 0.62, 95% CI 0.45-0.89). It was found that exclusive breastfeeding for six months or more is a protective factor against overweight in children in the second year of life living in the Brazilian semi-arid region.
ABSTRACT
BACKGROUND:Pathophysiological mechanisms after spinal cord injury are very complex, so there is no compressive and in-depth understanding on it. OBJECTIVE:To study the effect of dura mater spinalis integrity on cytokine levels in the cerebrospinal fluid of animal models of spinal cord injury. METHODS:The white rabbit models of spinal cord injury were established using clamp compression method, and then the models were randomly divided into four groups:no dura mater spinalis defect group, dura mater spinalis defect group, dura mater spinalis defect composite with membrane repairing group and dura mater spinalis defect composite with autologous fascia repair group. Enzyme-linked immunosorbent assay was performed to detect the changes of levels of cytokines (interleukin-6, interleukin-10 and tumor necrosis factorα) in the cerebrospinal fluid at 30 minutes, 1, 3, 6, 12 and 36 hours after surgery. RESULTS AND CONCLUSION:The levels of interleukin-6, interleukin-10 and tumor necrosis factorαin the cerebrospinal fluid of the dura mater spinalis defect group, dura mater spinalis defect composite with membrane repairing group and dura mater spinalis defect composite with autologous fascia repair group were significantly lower than those of the no dura mater spinalis defect group at 6 hours after surgery (P0.05). The results indicate that maintaining the integrity of dura mater spinalis of the spinal cord injury model can affect the levels of interleukin-6, interleukin-10 and tumor necrosis factorαin the cerebrospinal fluid, thus inhibiting the inflammatory response.
ABSTRACT
BACKGROUND: Telomere-associated proteins wil directly affect the function of telomeres, adjust the length of telomeric DNA, which are closely related with cellsenescence and carcinogenesis. OBJECTIVE: To find the key regulatory molecules in the cellsenescence process through observing the telomere-associated factor expression in normal cel replicative senescence process. METHODS: Based on established cel replicative senescence model, reverse transcription-PCR and western blot were used to detect the telomere-associated factor expression on the molecular and protein levels, including the telomere-associated factor human telomere binding protein 1, tankyrase 1, telomerase RNA, telomere protection protein 1 and P53 expressions in the human embryonic lung fibroblast replicative senescence. RESULTS AND CONCLUSION: The results showed that with the cellsenescence, transcription of human telomere binding protein 1 did not changed, while the protein expression of human telomere binding protein 1 was increased gradual y and then decreased rapidly; mRNA and protein expressions of telomere protection protein 1 did not changed; with the human embryonic lung fibroblast replicative senescence, expression of telomere protection protein 1 was decreased gradual y; with cellsenescence, telomerase RNA component showed an increasing trend; protein expression of P53 did not changed. Human telomere binding protein 1, telomere protection protein 1 and telomerase RNA play an important role in cellsenescence.
ABSTRACT
BACKGROUND: Previous studies have found that nerve growth factors play an important role in the process of wound healing, but there is less research for the low-affinity nerve growth factor receptor p75 and sortilin in fibroblasts, and no reports on whether there are differences in expression of p75 and sortilin in the scar fibroblasts and normal skin fibroblasts. OBJECTIVE: To study the expression of low-affility nerve growth factor receptor p75 and sortilin in the normal human skin fibroblasts and the human keloid fibroblasts. METHODS: The keloid fibroblasts and normal hunman skin fibroblasts were cultured in vitro, and the immortalized epithelial cells HaCaT were used as the positive control. The real-time PCR was used to detect the mRNA expression of the p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts, and western blot and immunocytochemical staining were used to detect the protein expression of p75 and sortilin. RESULTS AND CONCLUSION: The real-time PCR and western blot results showed that in the protein and mRNA levels, p75 and sortilin showed positive expression in the keloid fibroblasts and normal human skin fibroblasts, and there was no significant difference in the expression of p75 between keloid fibroblasts and normal human skin fibroblasts, and the expressions of p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts were significantly lower than those in HaCaT. There was no significant difference of p75 expression between keloid fibroblasts and normal human skin fibroblasts, and the expression of sortilin in the keloid fibroblasts was significantly lower than that in the normal human skin fibroblasts (P < 0.05). Immunocytochemical staining result showed that the expression of p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts were distributed in the membrane and cytoplasm. Precursor nerve growth factor combined with high-affinity p75 receptor could promote the apoptosis of the cells with the help of sortilin, and the expression of sortilin in the keloid fibroblasts was significantly lower than that in the normal human skin fibroblasts, which may associated with the high proliferation of the keloid fibroblasts. The results provide a new target for the prevention and treatment of pathological scars.
ABSTRACT
BACKGROUND: The cel density is one of the factors involved in the state of cel differentiation, and the effect of cel density on transforming growth factor-β1-induced epithelial-mesenchymal transition of HaCaT cells is stil unclear. OBJECTIVE: To observe the effect of cel density on transforming growth factor-β1-induced epithelial-mesenchymal transition of HaCaT cells. METHODS: HaCaT cells was seeded in 6-wel plates at low density of 103/cm2 and high density of 105/cm2 then treated by 2 μg/L transforming growth factor-β1 for 48 hours, thereafter observed the changes in cel morphology. The transcription levels of epithelial cadherin, tight junction protein-1, vimentin, neuronal-cadherin were detected by real-time PCR, and expression levels of epithelial cadherin and vimentin were detected by Western blot. RESULTS AND CONCLUSION: Cel gap of HaCaT cells grew larger after treated with transforming growth factor-β1 for 48 hours, and cel morphology was long spindle rather than polygonal in low-density group, while in high-density group without obvious morphological changes. The real-time PCR showed that the transcriptions of epithelial cel marker epithelial cadherin and tight junction protein-1 were suppressed when compared with the control group (P < 0.05), and the decreasing deree in the high-density group was higher than that in the low-density group (P <0.05), mesenchymal cel marker neuronal-cadherin and vimentin were upregulated in the high-density group and the low-density group when compared with the control group (P < 0.05), and there were no significant differences between high-density group and low-density group. Western blot results verified the changes of neuronal-cadherin and vimentin expression level. These results suggest that the high seeding density can inhibit transforming growth factor-β1-induced epithelial-mesenchymal transition of HaCaT cells.
ABSTRACT
Breastmilk provides the best optimal nutrition for infants, especially for the first few months of life. In breastmilk, there are innumerable immune protective and modulating factors. Also, the nutrients in breastmilk act as immune protective factors. The advantages of breastfeeding are not only for protection from infectious diseases, but also protection from some chronic disease, such as celiac disease, atopy, and obesity. A dose-response relationship of breastfeeding has been reported. For lifelong health, breastfeeding is the first step. In Korea, the majority of mothers obtain information about breastfeeding from internet searching, books and magazines. Physicians should actively and enthusiastically recommend breastfeeding and provide detailed advice and integral information about breastfeeding.