Protective role of melatonin in ultraviolet radiation- induced oxidative stress in human skin photoaging

The ultraviolet radiation of the sun that reaches the earth is made up of ultraviolet A (95%) and ultraviolet B (5%). Exposure to ultraviolet radiation (UVR) is the main factor in photoaging. Chronic exposure to sunlight acts as an environmental stressor, leading to oxidative damage or stress. Oxidative damage stimulates the accumulation of free radicals, such as reactive oxygen species (ROS) or reactive nitrogen species (RNS) that are responsible for premature skin aging. Photoaged skin is characterized externally by irregular pigmentation, wrinkles, and reduced skin elasticity, and internally by the breakdown of dermal collagen and elastin. Free radicals can be scavenged and the skin can be protected from further oxidative damage by antioxidants. Melatonin is a hormone produced mainly by the pineal gland, as well as many other organs, including the skin. One of the functions of melatonin is exerted by the antioxidative melatoninergic system to prevent ultraviolet (UV)-induced skin photoaging. The aim of this review was to study the protective effect of melatonin on skin photoaging resulting from UVR exposure. The references were tracked using various databases, such as Google Scholar and PubMed with regard to publications in English for the last 5 years (2019-2023). Melatonin inhibits UVR-induced aging in multiple ways, such as protecting skin cells, binding free radicals, accelerating the activity of antioxidant enzymes, preventing increased mitochondrial membrane permeability, and assisting electron transport efficiency in the mitochondrial respiratory chain. Exogenous application of melatonin is usually by the oral route, but for localized effects on the skin, topical administration is recommended, with consideration of preparations with a better half-life and bioavailability. Understanding the protective antioxidant function of melatonin in UV-induced skin photoaging helps to optimize its application. The protective properties of melatonin against UVR-oxidative stress-induced photoaging will be further explored in this review

Potensi Permainan Papan Edukasi Aktif Kutus PHBS Sebagai Modalitas Pencegahan Obesitas Anak

Introduction; lifestyle changes and lack of information about PHBS (The Clean and Healthy Behavior) or balanced nutrition are triggers for obesity. Purpose: To determine the potential of active education cutus board games for clean and healthy behavior to prevent obesity in children. Methods: Study literature articles in the last 10 years using keywords accessed from the Cochrane browser, NCBI, Google scholar, and Garuda. Result; Clean and Healthy Behavior active education board game is easy to play, cheap, has 2-way interaction and has a learning pattern by doing where children are required to find solutions when playing. Conclusion; The educational board game cutus active Clean and Healthy Behavior improves children's knowledge and behavior to prevent obesity in childrenPendahuluan; perubahan gaya hidup dan kurangnya informasi tentang PHBS (The Clean and Healthy Behavior) atau gizi seimbang menjadi pemicu terjadinya obesitas. Tujuan: mengetahui potensi permainan papan edukasi cutus aktif perilaku bersih dan sehat untuk mencegah obesitas pada anak. Metode: Studi literatur artikel dalam 10 tahun terakhir menggunakan kata kunci yang diakses dari browser Cochrane, NCBI, Google scholar, dan Garuda. Hasil; Permainan papan edukasi cutus aktif Perilaku Bersih dan Sehat mudah dimainkan, murah, memiliki interaksi 2 arah, dan memiliki pola belajar dengan melakukan dimana anak dituntut untuk mencari solusi saat bermain. Kesimpulan; Permainan papan edukasi cutus aktif Perilaku Bersih dan Sehat meningkatkan pengetahuan dan perilaku anak untuk mencegah terjadinya obesitas pada ana

Complete genome sequence of the industrial bacterium Bacillus licheniformis and comparisons with closely related Bacillus species

BACKGROUND: Bacillus licheniformis is a Gram-positive, spore-forming soil bacterium that is used in the biotechnology industry to manufacture enzymes, antibiotics, biochemicals and consumer products. This species is closely related to the well studied model organism Bacillus subtilis, and produces an assortment of extracellular enzymes that may contribute to nutrient cycling in nature. RESULTS: We determined the complete nucleotide sequence of the B. licheniformis ATCC 14580 genome which comprises a circular chromosome of 4,222,336 base-pairs (bp) containing 4,208 predicted protein-coding genes with an average size of 873 bp, seven rRNA operons, and 72 tRNA genes. The B. licheniformis chromosome contains large regions that are colinear with the genomes of B. subtilis and Bacillus halodurans, and approximately 80% of the predicted B. licheniformis coding sequences have B. subtilis orthologs. CONCLUSIONS: Despite the unmistakable organizational similarities between the B. licheniformis and B. subtilis genomes, there are notable differences in the numbers and locations of prophages, transposable elements and a number of extracellular enzymes and secondary metabolic pathway operons that distinguish these species. Differences include a region of more than 80 kilobases (kb) that comprises a cluster of polyketide synthase genes and a second operon of 38 kb encoding plipastatin synthase enzymes that are absent in the B. licheniformis genome. The availability of a completed genome sequence for B. licheniformis should facilitate the design and construction of improved industrial strains and allow for comparative genomics and evolutionary studies within this group of Bacillaceae

IgA, B Cells and Epithelial Cells in Mucosal Immunity

Our mucosal immune system responds to pathogens and commensals on mucosal surfaces by forming a tight barrier and producing immunoglobulin A (IgA). IgA production depends on the uptake of gut lumen particulates by specialized epithelial cells called microfold (M) cells and the subsequent B cell activation in the mucosal lymphoid tissue. B-1 and B-2 B cells are two main B cell subset responsible in generating immune response at the mucosal site. Although B-1B cells has been shown to contribute to T- cell independent immune response while B-2 B cell use mainly T-cell dependent pathway, studies have suggested that both of these subset contribute IgA production in the gut almost equally. However, contrary to B-2 B cells, the location where B-1 B cell activated by mucosal antigen has remained unclear. Additionally, tumor necrosis factor (TNF) receptor/ligand superfamily signaling has been shown to play a role in mucosal lymphoid tissue organogenesis and M cell uptake function such that lymphotoxin (LT)-α-/-, LT-β-/-, LT-βR-/- or CD137-/- mice have no Peyer's patches or a very low IgA titer. In-vitro treatment with TNFα is also known to decrease epithelial barrier function. Henceforth, this study will highlight the potential use of recombinant IgA in clearing the replicating dengue virus in the gut, the B-1 B cell contribution in mucosal immune response, and the role of a TNF superfamily receptor, CD137, in the intestinal epithelial cells. Peritoneal B-1 B cells generate antigen specific IgG and IgM when the mice immunized intraperitoneally or subcutaneously, but not intranasally, using polymeric vaccine. The last chapter of this study further characterizes the role of CD137 in intestinal epithelial cells by utilizing an in-vitro overexpression system, which could further reveal the biological relevance of TNFα in chronic intestinal inflammation. Our seminal findings describe the role of CD137 in increasing tight junction resistance and its association with actin filament termini. In sum, this study addresses how a receptor, CD137, known for its co-stimulatory function in immune cells activation can mediate the physical barrier created by intestinal epithelial cells, the humoral response of B-1 B cells in mucosal immunity and the use of recombinant IgA as therapy

Hybrid flagellin as a T cell independent vaccine scaffold.

BackgroundTo extend the potency of vaccines against infectious diseases, vaccines should be able to exploit multiple arms of the immune system. One component of the immune system that is under-used in vaccine design is the subset of B cells known to be capable of responding to repetitive antigenic epitopes and differentiate into plasma cells even in the absence of T cell help (T-independent, TI).ResultsTo target vaccine responses from T-independent B cells, we reengineered a bacterial Flagellin (FliC) by replacing its exposed D3 domain with a viral envelope protein from Dengue virus (DENV2). The resulting hybrid FliC protein (hFliC) was able to form stable filaments decorated with conformationally intact DENV2 envelope domains. These filaments were not only capable of inducing a T cell-dependent (TD) humoral antibody response, but also significant IgM and IgG3 antibody response in a helper T cell repertoire-restricted transgenic mouse model.ConclusionsOur results provide proof-of-principle demonstration that a reengineered hybrid FliC could be used as a platform for polymeric subunit vaccines, enhancing T cell-dependent and possibly inducing T-independent antibody responses from B-1 B cells as well

M cell-derived vesicles suggest a unique pathway for trans-epithelial antigen delivery

M cells are a subset of mucosal epithelial cells with specialized capability to transport antigens across the mucosal barrier, but there is limited information on antigen transfer in the subepithelial zone due to the challenges in tracking microparticles and antigens that are transcytosed by this unique cell. Using transgenic reporter mice expressing dsRed in the cytoplasm of M cells and EGFP in myeloid cells, we observed that the M cell basolateral pocket hosts a close interaction between B lymphocytes and dendritic cells. Interestingly, we identified a population of previously undescribed M cell-derived vesicles (MCM) that are constitutively shed into the subepithelial space and readily taken up by CX(3)CR1(+)CD11b(+) CD11c(+) dendritic cells. These MCM are characterized by their cytoplasmic dsRed confirming their origin from the M cell cytoplasm. MCM showed preferential colocalization in dendritic cells with transcytosed bacteria but not transcytosed polystyrene beads, indicating a selective sorting of cargo fate in the subepithelial zone. The size and number of MCM were found to be upregulated by bacterial transcytosis and soluble toll-like receptor 2 (TLR2) agonist, further pointing to dynamic regulation of this mechanism. These results suggest that MCM provide a unique function by delivering to dendritic cells, various materials such as M cell-derived proteins, effector proteins, toxins, and particles found in the M cell cytoplasm during infection or surveillance

Ligand-induced sequestering of branchpoint sequence allows conditional control of splicing-6

Ning mutations within core TBA). Cells were treated with buffer (lanes 4 and 6) or with 1 mM theophylline (lanes 5 and 7). The product of RT-PCR assays of total RNA isolated from each well was analyzed on a 2.5% agarose gel to estimate the effect of theophylline on the efficiency of exon 2 alternative splicing. The PCR amplified bands corresponding to exon 2 included or excluded mRNA is indicated. (B) The internal exon 2 exclusion: inclusion ratio for ABT4M or ABT4Mmu in the absence (open box) or presence of theophylline (shaded box) is shown. The data represent mean ± SEM. * < 0.04 versus mutant is significant.<p><b>Copyright information:</b></p><p>Taken from "Ligand-induced sequestering of branchpoint sequence allows conditional control of splicing"</p><p>http://www.biomedcentral.com/1471-2199/9/23</p><p>BMC Molecular Biology 2008;9():23-23.</p><p>Published online 12 Feb 2008</p><p>PMCID:PMC2275289.</p><p></p