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Toxins Dec 2021β-defensins are antimicrobial peptides presenting in vertebrate animals. They participate in innate immunity, but little is known about them in reptiles, including...
β-defensins are antimicrobial peptides presenting in vertebrate animals. They participate in innate immunity, but little is known about them in reptiles, including snakes. Although several β-defensin genes were described in Brazilian snakes, their function is still unknown. The peptide sequence from these genes was deduced, and synthetic peptides (with approximately 40 amino acids and derived peptides) were tested against pathogenic bacteria and fungi using microbroth dilution assays. The linear peptides, derived from β-defensins, were designed applying the bioisosterism strategy. The linear β-defensins were more active against , , , and . The derived peptides (7-14 mer) showed antibacterial activity against those bacteria and on . Nonetheless, they did not present activity against , , , and showing that the cysteine substitution to serine is deleterious to antifungal properties. Tryptophan residue showed to be necessary to improve antibacterial activity. Even though the studied snake β-defensins do not have high antimicrobial activity, they proved to be attractive as template molecules for the development of antibiotics.
Topics: Animals; Anti-Infective Agents; Bacteria; Fungi; Reptilian Proteins; Snakes; Species Specificity; beta-Defensins
PubMed: 35050978
DOI: 10.3390/toxins14010001 -
International Journal of Cosmetic... Aug 2022Facial skin is a particularly complex environment made of different skin types such as sebaceous (forehead) and dry (cheeks). The skin microbiota composition on... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Facial skin is a particularly complex environment made of different skin types such as sebaceous (forehead) and dry (cheeks). The skin microbiota composition on different facial sites has not yet been addressed.
METHODS
We conducted a 4-week-long, single-centre, randomized and placebo-controlled clinical study involving 23 Caucasian females. We assessed both bacterial composition on five different facial areas and the microbiome modulatory effects resulting from the topical application of a plant extract (Epilobium fleischeri). Skin microbiome samples were collected before and after 4 weeks of product application. Microbiota profiling was performed via 16S rRNA gene sequencing, and relative abundance data were used to calculate differentials via a multinomial regression model.
RESULTS
Via 'reference frames', we observed shifts in microbial composition after 4 weeks of twice-daily product application and identify certain microbiota species, which were positively associated with the application of the product containing the Epilobium fleischeri extract. Staphylococcus hominis, Staphylococcus epidermidis, and Micrococcus yunnanensis appeared to be significantly enriched in the final microbiota composition of the active treatment group.
CONCLUSION
Facial skin was found to be colonized by an heterogenous microbiota, and the Epilobium fleischeri extract had a modulatory effect on commensal bacteria on the different facial sites.
Topics: Bacteria; Cholestenone 5 alpha-Reductase; Female; Humans; Microbiota; Plant Extracts; RNA, Ribosomal, 16S; Skin
PubMed: 35499362
DOI: 10.1111/ics.12777 -
Marine Drugs Nov 2021Sunscreen and sunblock are crucial skincare products to prevent photoaging and photocarcinogenesis through the addition of chemical filters to absorb or block...
Sunscreen and sunblock are crucial skincare products to prevent photoaging and photocarcinogenesis through the addition of chemical filters to absorb or block ultraviolet (UV) radiation. However, several sunscreen and sunblock ingredients, mostly UV filters, have been associated with human and environmental safety concerns. Therefore, the exploration and discovery of promising novel sources of efficient and safer compounds with photoprotection-related activities are currently required. Marine invertebrates, particularly their associated microbiota, are promising providers of specialized metabolites with valuable biotechnological applications. Nevertheless, despite Actinobacteria members being a well-known source of bioactive metabolites, their photoprotective potential has been poorly explored so far. Hence, a set of methanolic extracts obtained from -derived actinomycetes was screened regarding their antioxidant and UV-absorbing capacities (i.e., photoprotection-related activities). The active extract-producing strains were identified and classified within genera and This is the first report of the isolation of these microorganisms from (an ecologically important Caribbean coral reef-boring sponge). The in vitro cytotoxicity on dermal fibroblasts of oxybenzone and the selected active extracts revealed that oxybenzone exerted a cytotoxic effect, whereas no cytotoxic effect of test extracts was observed. Accordingly, the most active (SPFi > 5, radical scavenging > 50%) and nontoxic (cell viability > 75%) extracts were obtained from strains. Finally, LC-MS-based characterization suggested a broad chemical space within the test strains and agreed with the reported streptomycetes' chemodiversity. The respective metabolite profiling exposed a strain-specific metabolite occurrence, leading to the recognition of potential hits. These findings suggest that marine produce photoprotectants ought to be further explored in skincare applications.
Topics: Actinobacteria; Animals; Antioxidants; Aquatic Organisms; Biphenyl Compounds; Caribbean Region; Coral Reefs; Fibroblasts; Humans; Picrates; Porifera; Sunscreening Agents; Ultraviolet Rays
PubMed: 34940673
DOI: 10.3390/md19120674 -
Scientific Reports Oct 2021In recent years' synthesis of metal nanoparticle using plants has been extensively studied and recognized as a non-toxic and efficient method applicable in biomedical...
In recent years' synthesis of metal nanoparticle using plants has been extensively studied and recognized as a non-toxic and efficient method applicable in biomedical field. The aim of this study is to investigate the role of different parts of medical plant Carduus crispus on synthesizing silver nanoparticles and characterize the produced nanoparticle. Our study showed that silver nanoparticles (AgNP) synthesized via whole plant extract exhibited a blue shift in absorption spectra with increased optical density, which correlates to a high yield and small size. Also, the results of zeta potential, X-ray diffraction, photon cross-correlation spectroscopy analysis showed the surface charge of - 54.29 ± 4.96 mV (AgNP-S), - 42.64 ± 3.762 mV (AgNP-F), - 46.02 ± 4.17 mV (AgNP-W), the crystallite size of 36 nm (AgNP-S), 13 nm (AgNP-F), 14 nm (AgNP-W) with face-centered cubic structure and average grain sizes of 145.1 nm, 22.5 nm and 99.6 nm. Another important characteristic, such as elemental composition and constituent capping agent has been determined by energy-dispersive X-ray spectroscopy and Fourier transform infrared. The silver nanoparticles were composed of ~ 80% Ag, ~ 15% K, and ~ 7.5% Ca (or ~ 2.8% P) elements. Moreover, the results of the FTIR measurement suggested that the distinct functional groups present in both AgNP-S and AgNP-F were found in AgNP-W. The atomic force microscopy analysis revealed that AgNP-S, AgNP-F and AgNP-W had sizes of 131 nm, 33 nm and 70 nm respectively. In addition, the biosynthesized silver nanoparticles were evaluated for their cytotoxicity and antibacterial activity. At 17 µg/ml concentration, AgNP-S, AgNP-F and AgNP-W showed very low toxicity on HepG2 cell line but also high antibacterial activity. The silver nanoparticles showed antibacterial activity on both gram-negative bacterium Escherichia coli (5.5 ± 0.2 mm to 6.5 ± 0.3 mm) and gram-positive bacterium Micrococcus luteus (7 ± 0.4 mm to 7.7 ± 0.5 mm). Our study is meaningful as a first observation indicating the possibility of using special plant organs to control the characteristics of nanoparticles.
Topics: Anti-Bacterial Agents; Carduus; Escherichia coli; Hep G2 Cells; Humans; Metal Nanoparticles; Micrococcus luteus; Silver
PubMed: 34702916
DOI: 10.1038/s41598-021-00520-2 -
Microbial Pathogenesis Feb 2020Studies on understanding the human microbiome continue to grow rapidly; nonetheless, reports on alterations in the microbiome post HIV infection are limited. Human...
Studies on understanding the human microbiome continue to grow rapidly; nonetheless, reports on alterations in the microbiome post HIV infection are limited. Human microbiome is an aggregate of bacteria, fungi, viruses and archaea that have co-evolved with humans. These microbes have important roles in immune modulation, vitamin synthesis, metabolism etc. The human pharyngeal microbiome, which resides in the junction between digestive and respiratory tracts, might have a key role in the prevention of respiratory tract infections, akin to the actions of the intestinal microbiome against enteric infections. The respiratory tract is constantly exposed to various environmental and endogenous microbes; however, unlike other similar mucosal surfaces, there has been limited investigation of the microbiome of the respiratory tract. HIV infection is associated with alterations in the respiratory microbiome. The aim of this study was to use next-generation sequencing to determine the composition of the oropharyngeal microbiome in a HIV-positive individual. The bacterial composition was determined by illumina sequencing using MiSeq of partial 16S rRNA genes (V3-V4). A total of 3, 57,926 reads were analyzed. Overall, the genera Proteus, Enterococcus, Bacteroides, Prevotella and Clostridium were most prevalent bacterial populations in the oropharynx of an HIV positive patient.
Topics: Bacteroides; Clostridium; DNA, Bacterial; Enterococcus; Gastrointestinal Microbiome; HIV Infections; High-Throughput Nucleotide Sequencing; Humans; Microbiota; Micrococcus; Oropharynx; Pharynx; Phylogeny; Prevotella; Proteus; RNA, Ribosomal, 16S; Respiratory System; Respiratory Tract Infections; Sequence Analysis, DNA
PubMed: 31790791
DOI: 10.1016/j.micpath.2019.103805 -
Dose-response : a Publication of... 2022The aim of this study was to evaluate antioxidant and antimicrobial potential of fruit. Ethanolic extract was prepared and phytochemical screening showed the presence...
The aim of this study was to evaluate antioxidant and antimicrobial potential of fruit. Ethanolic extract was prepared and phytochemical screening showed the presence of a lot of chemical compounds. Fourier transform infrared spectroscopy (FTIR) spectra indicated the presence of organic acids, hydroxyl and phenolic compounds, amino groups, aliphatic compounds, and functional groups such as amide, ketone, aldehyde, aromatics, and halogen compounds. Antioxidant activity of the ethanolic extract of by the DPPH method showed 71.4% inhibition, whereas IC ± SEM (μg/mL) was .406 ± .11. Antibacterial activity was performed against Maximum antibacterial activity was exhibited by , and it was Antifungal activity was performed against Ethanolic extract of showed antifungal activity against ± 1 mm) 4 ± 1 mm) Aspergillus ( ± 1 mm), whereas no activity was exhibited by . Further research is needed in order to evaluate the cytotoxic effects of as well.
PubMed: 36106057
DOI: 10.1177/15593258221126832 -
PLoS Genetics Oct 2022Immune memory is the ability of organisms to elicit potentiated immune responses at secondary infection. Current studies have revealed that similar to adaptive immunity,...
Immune memory is the ability of organisms to elicit potentiated immune responses at secondary infection. Current studies have revealed that similar to adaptive immunity, innate immunity exhibits memory characteristics (called "innate immune memory"). Although epigenetic reprogramming plays an important role in innate immune memory, the underlying mechanisms have not been elucidated, especially at the individual level. Here, we established experimental systems for detecting innate immune memory in Drosophila melanogaster. Training infection with low-pathogenic bacteria enhanced the survival rate of the flies at subsequent challenge infection with high-pathogenic bacteria. Among low-pathogenic bacteria, Micrococcus luteus (Ml) and Salmonella typhimurium (St) exerted apparent training effects in the fly but exhibited different mechanisms of action. Ml exerted training effects even after its clearance from flies, while live St persisted in the flies for a prolonged duration. RNA sequencing (RNA-Seq) analysis revealed that Ml training enhanced the expression of the immune-related genes under the challenge condition but not under the non-challenge condition. In contrast, St training upregulated the expression of the immune-related genes independent of challenge. These results suggest that training effects with Ml and St are due to memory and persistence of immune responses, respectively. Furthermore, we searched for the gene involved in immune memory, and identified a candidate gene, Ada2b, which encodes a component of the histone modification complex. The Ada2b mutant suppressed Ml training effects on survival and disrupted the expression of some genes under the training + challenge condition. These results suggest that the gene expression regulated by Ada2b may contribute to innate immune memory in Drosophila.
Topics: Animals; Drosophila; Drosophila melanogaster; Transcriptome; Immunologic Memory; Drosophila Proteins; Immunity, Innate
PubMed: 36252180
DOI: 10.1371/journal.pgen.1010005 -
Mobile phones in the orthopedic operating room: Microbial colonization and antimicrobial resistance.World Journal of Orthopedics May 2020Surgical site infections are a major cause of morbidity and mortality following orthopedic surgery. Recent efforts to identify sources of contamination in the operating... (Review)
Review
BACKGROUND
Surgical site infections are a major cause of morbidity and mortality following orthopedic surgery. Recent efforts to identify sources of contamination in the operating rooms have implicated mobile phones.
AIM
To investigate microbial colonization on the mobile phones of health care professionals in the orthopedic operating room.
METHODS
We conducted a cross-sectional study involving culture and sensitivity analysis of swabs taken from the mobile phones of orthopedic and anesthesia attendings, residents, technicians and nurses working in the orthopedic operating rooms over a period of two months. Demographic and cell phone related factors were recorded using a questionnaire and the factors associated with contamination were analyzed.
RESULTS
Ninety-three of 100 mobile phones were contaminated. Species isolated were (62%), Micrococcus (41%) and Bacillus (26%). The risk of contamination was increased with mobile covers and cracked screens and decreased by cell phone cleaning.
CONCLUSION
Mobile phones belonging to health care workers are frequently contaminated with pathogenic bacteria with the potential of transferring drug resistance to nosocomial pathogens. Studies investigating the relationship to surgical site infections need to be conducted. The concept of "mobile hygiene" involving the change of mobile covers, replacement of cracked screens or even wiping the phone with an alcohol swab could yield the cost-effective balance that contaminated cell phones deserve until they are established as a direct cause of surgical site infections.
PubMed: 32477902
DOI: 10.5312/wjo.v11.i5.252 -
American Journal of Infection Control Apr 2023Kinesio tapes (KTs) are tapes used in physical therapy and athletics. We sought to evaluate if wearing KTs for extended periods of time increases exposure to antibiotic...
BACKGROUND
Kinesio tapes (KTs) are tapes used in physical therapy and athletics. We sought to evaluate if wearing KTs for extended periods of time increases exposure to antibiotic resistant opportunistic pathogens and/or effects normal human skin bacteria.
METHODS
The study consisted of 10 volunteers wearing 9 KTs on their arms for 5 consecutive days. Microorganisms were isolated from fragments collected on the second and fifth day then analyzed. Bacteria were identified using the BIOLOG system. Resistance to selected antibiotics was performed using E-Test. The effect of KTs on the growth of Staphylococcus aureus, Staphylococcus epidermidis, and Micrococcus luteus was evaluated in a diffusion-based assay.
RESULTS
We found that KTs accumulated environmental bacteria. Among 22 species 8 were opportunistic pathogens, and all of them exhibited resistance to at least one antibiotic. None of the tapes produced inhibition zones against S. aureus. One tape, Leukotape P, caused growth inhibition in non-pathogenic S. epidermidis and M. luteus. The adhesive material of the tapes inhibited the growth of all tested bacteria.
CONCLUSIONS
These results indicate that KTs may increase the exposure to antibiotic resistant pathogens which can accumulate from the environment. Further, extended exposure could lead to changes in normal skin microbiota, potentially contributing to increased risks of skin infections.
Topics: Humans; Staphylococcus aureus; Athletic Tape; Skin; Anti-Bacterial Agents; Staphylococcus epidermidis
PubMed: 35870663
DOI: 10.1016/j.ajic.2022.06.027 -
Huan Jing Ke Xue= Huanjing Kexue May 2023In order to denitrify the urban tail water deeply and control the eutrophication of surface water, the molecular biology methods were used to study the nitrogen...
In order to denitrify the urban tail water deeply and control the eutrophication of surface water, the molecular biology methods were used to study the nitrogen metabolism performance of the denitrification complex flora and the algal-bacteria symbiotic system. The results showed that the nitrogen metabolism complex flora was high ammonification and denitrification performance. The removal effect of ammonia nitrogen of group JZ was very well in urban tailwater, and the degradation rate was as high as 95%. The removal effect of total nitrogen of group JZ was better than that of group J in the experimental water distribution. High-throughput sequencing showed that the main dominant flora and proportion of group J were Firmicutes 44.53%, Proteobacteria 43.41%, Actinobacteria 5.37%, Bacteroidetes 3.04%, and Chloroflexi 1.35%. The main dominant bacterial groups in the group JZ were 33.89% Cyanobacteria, 25.34% Chloroflexi, 19.38% Proteobacteria, 10.02% Firmicutes, and 4.20% Acidobacteria. The dominant species in group J were compared with those in group JZ; the proportions were 82% and 18% in Firmicutes, 69% and 31% in Proteobacteria, 1% and 99% in Cyanobacteria, 5.1% and 95% in Chloroflexi, 73% and 27% in Actinobacteria. It was concluded that the removal effect of ammonia nitrogen of group JZ was high in the urban tailwater. With the addition and growth of Micrococcus in group J, the nitrogen metabolism flora in group JZ changed accordingly, so as to adapt to the environment in which the dominant algae formed. It forms a new nitrogen metabolism system of bacteria and algae with Micrococcus. This research provides a theoretical and data basis for the application of algal-bacterial co-metabolism systems.
Topics: Ammonia; Cyanobacteria; Acidobacteria; Proteobacteria; Nitrogen
PubMed: 37177968
DOI: 10.13227/j.hjkx.202206265