RÉSUMÉ
Acinetobacter baumannii, which is resistant to multiple drugs, is an opportunistic pathogen responsible for severe nosocomial infections. With no antibiotics available, phages have obtained clinical attention. However, since immunocompromised patients are often susceptible to infection, the appropriate timing of administration is particularly important. During this research, we obtained a lytic phage vB_AbaM_P1 that specifically targets A. baumannii. We then assessed its potential as a prophylactic treatment for lung infections caused by clinical strains. The virus experiences a period of inactivity lasting 30 min and produces approximately 788 particles during an outbreak. Transmission electron microscopy shows that vB_AbaM_P1 was similar to the Saclayvirus. Based on the analysis of high-throughput sequencing and bioinformatics, vB_AbaM_P1 consists of 107537 bases with a G + C content of 37.68%. It contains a total of 177 open reading frames and 14 tRNAs. No antibiotic genes were detected. In vivo experiments, using a cyclophosphamide-induced neutrophil deficiency model, tested the protective effect of phage on neutrophil-deficient rats by prophylactic application of phage. The use of phages resulted in a decrease in rat mortality caused by A. baumannii and a reduction in the bacterial burden in the lungs. Histologic examination of lung tissue revealed a decrease in the presence of immune cells. The presence of phage vB_AbaM_P1 had a notable impact on preventing A. baumannii infection, as evidenced by the decrease in oxidative stress in lung tissue and cytokine levels in serum. Our research offers more robust evidence for the early utilization of bacteriophages to mitigate A. baumannii infection. KEY POINTS: â¢A novel Saclayvirus phage infecting A. baumannii was isolated from sewage. â¢The whole genome was determined, analyzed, and compared to other phages. â¢Assaying the effect of phage in preventing infection in neutrophil-deficient models.
Sujet(s)
Infections à Acinetobacter , Acinetobacter baumannii , Bactériophages , Génome viral , Acinetobacter baumannii/virologie , Acinetobacter baumannii/génétique , Animaux , Infections à Acinetobacter/prévention et contrôle , Infections à Acinetobacter/microbiologie , Bactériophages/génétique , Bactériophages/isolement et purification , Bactériophages/physiologie , Rats , Phagothérapie/méthodes , Composition en bases nucléiques , Modèles animaux de maladie humaine , Génomique , Séquençage nucléotidique à haut débit , Poumon/virologie , Poumon/microbiologie , Pneumopathie infectieuse/prévention et contrôle , Pneumopathie infectieuse/microbiologie , Pneumopathie infectieuse/virologie , MâleRÉSUMÉ
Salmonella, a prominent foodborne pathogen, has posed enduring challenges to the advancement of food safety and global public health. The escalating concern over antibiotic misuse, resulting in the excessive presence of drug residues in animal-derived food products, necessitates urgent exploration of alternative strategies for Salmonella control. Bacteriophages emerge as promising green biocontrol agents against pathogenic bacteria. This study delineates the identification of two novel virulent Salmonella phages, namely phage vB_SalS_ABTNLsp11241 (referred to as sp11241) and phage 8-19 (referred to as 8-19). Both phages exhibited efficient infectivity against Salmonella enterica serotype Enteritidis (SE). Furthermore, this study evaluated the effectiveness of two phages to control SE in three different foods (whole chicken eggs, raw chicken meat, and lettuce) at different MOIs (1, 100, and 10000) at 4°C. It's worth noting that sp11241 and 8-19 achieved complete elimination of SE on eggs after 3 h and 6 h at MOI = 100, and after 2 h and 5 h at MOI = 10000, respectively. After 12 h of treatment with sp11241, a maximum reduction of 3.17 log10 CFU/mL in SE was achieved on raw chicken meat, and a maximum reduction of 3.00 log10 CFU/mL was achieved on lettuce. Phage 8-19 has the same effect on lettuce as sp11241, but is slightly less effective than sp11241 on chicken meat (a maximum 2.69 log10 CFU/mL reduction). In conclusion, sp11241 and 8-19 exhibit considerable potential for controlling Salmonella contamination in food at a low temperature and represent viable candidates as green antibacterial agents for food applications.
Sujet(s)
Poulets , Oeufs , Microbiologie alimentaire , Lactuca , Viande , Phages de Salmonella , Salmonella enteritidis , Lactuca/microbiologie , Animaux , Oeufs/microbiologie , Oeufs/virologie , Poulets/microbiologie , Salmonella enteritidis/virologie , Viande/microbiologie , Sécurité des aliments , Contamination des aliments/prévention et contrôle , VirulenceRÉSUMÉ
Acinetobacter baumannii, an opportunistic pathogen, poses a significant threat in intensive care units, leading to severe nosocomial infections. The rise of multi-drug-resistant strains, particularly carbapenem-resistant A. baumannii, has created formidable challenges for effective treatment. Given the prolonged development cycle and high costs associated with antibiotics, phages have garnered clinical attention as an alternative for combating infections caused by drug-resistant bacteria. However, the utilization of phage therapy encounters notable challenges, including the narrow host spectrum, where each phage targets a limited subset of bacteria, increasing the risk of phage resistance development. Additionally, uncertainties in immune system dynamics during treatment hinder tailoring symptomatic interventions based on patient-specific states. In this study, we isolated two A. baumannii phages from wastewater and conducted a comprehensive assessment of their potential applications. This evaluation included sequencing analysis, genome classification, pH and temperature stability assessments, and in vitro bacterial inhibition assays. Further investigations involved analyzing histological and cytokine alterations in rats undergoing phage cocktail treatment for pneumonia. The therapeutic efficacy of the phages was validated, and transcriptomic studies of rat lung tissue during phage treatment revealed crucial changes in the immune system. The findings from our study underscore the potential of phages for future development as a treatment strategy and offer compelling evidence regarding immune system dynamics throughout the treatment process.IMPORTANCEDue to the growing problem of multi-drug-resistant bacteria, the use of phages is being considered as an alternative to antibiotics, and the genetic safety and application stability of phages determine the potential of phage application. The absence of drug resistance genes and virulence genes in the phage genome can ensure the safety of phage application, and the fact that phage can remain active in a wide range of temperatures and pH is also necessary for application. In addition, the effect evaluation of preclinical studies is especially important for clinical application. By simulating the immune response situation during the treatment process through mammalian models, the changes in animal immunity can be observed, and the effect of phage therapy can be further evaluated. Our study provides compelling evidence that phages hold promise for further development as therapeutic agents for Acinetobacter baumannii infections.
Sujet(s)
Infections à Acinetobacter , Acinetobacter baumannii , Bactériophages , Carbapénèmes , Modèles animaux de maladie humaine , Phagothérapie , Acinetobacter baumannii/virologie , Acinetobacter baumannii/effets des médicaments et des substances chimiques , Animaux , Infections à Acinetobacter/thérapie , Infections à Acinetobacter/microbiologie , Rats , Phagothérapie/méthodes , Carbapénèmes/pharmacologie , Bactériophages/physiologie , Bactériophages/génétique , Antibactériens/pharmacologie , Antibactériens/usage thérapeutique , Multirésistance bactérienne aux médicaments , Mâle , Génome viral , Eaux usées , Pneumopathie infectieuse/thérapie , Pneumopathie infectieuse/microbiologie , Pneumopathie infectieuse/virologieRÉSUMÉ
Mycotoxins, ubiquitous contaminants in food, present a global threat to human health and well-being. Mitigation efforts, such as the implementation of sound agricultural practices, thorough food processing, and the advancement of mycotoxin control technologies, have been instrumental in reducing mycotoxin exposure and associated toxicity. To comprehensively assess mycotoxins and their toxicodynamic implications, the deployment of effective and predictive strategies is imperative. Understanding the manner of action, transformation, and cumulative toxic effects of mycotoxins, moreover, their interactions with food matrices can be gleaned through gene expression and transcriptome analyses at cellular and molecular levels. MicroRNAs (miRNAs) govern the expression of target genes and enzymes that play pivotal roles in physiological, pathological, and toxicological responses, whereas acute phase proteins (APPs) exert regulatory control over the metabolism of therapeutic agents, both endogenously and posttranscriptionally. Consequently, this review aims to consolidate current knowledge concerning the regulatory role of miRNAs in the initiation of toxicological pathways by mycotoxins and explores the potential of APPs as biomarkers following mycotoxin exposure. The findings of this research highlight the potential utility of miRNAs and APPs as indicators for the detection and management of mycotoxins in food through biological processes. These markers offer promising avenues for enhancing the safety and quality of food products.
Sujet(s)
microARN , Mycotoxines , Humains , Mycotoxines/analyse , microARN/génétique , Contamination des aliments/analyse , Protéine de la phase aigüeRÉSUMÉ
Mycotoxins are common in many agricultural products and may harm both animals and humans. Dietary mycotoxins are reduced via physical, chemical, and thermal decontamination methods. Chemical residues are left behind after physical and chemical treatments that decrease food quality. Since mycotoxins are heat-resistant, heat treatments do not completely eradicate them. Cold plasma therapy increases food safety and shelf life. Cold plasma-generated chemical species may kill bacteria quickly at room temperature while leaving no chemical residues. This research explains how cold plasma combats mold and mycotoxins to guarantee food safety and quality. Fungal cells are damaged and killed by cold plasma species. Mycotoxins are also chemically broken down by the species, making the breakdown products safer. According to a preliminary cold plasma study, plasma may enhance food shelf life and quality. The antifungal and antimycotoxin properties of cold plasma benefit fresh produce, agricultural commodities, nuts, peppers, herbs, dried meat, and fish.
Sujet(s)
Mycotoxines , Gaz plasmas , Humains , Mycotoxines/analyse , Gaz plasmas/composition chimique , Contamination des aliments/prévention et contrôle , Contamination des aliments/analyse , Champignons , Sécurité des alimentsRÉSUMÉ
This study was planned to detect the adverse pathological consequences of aflatoxin B1 in White Leghorn (WLH) layer breeder males. Eight-week-old male layer cockerels were separated into six experimental categories: A group was kept as negative control, offered with normal feed only; group B was fed with 400 ppb amount of aflatoxin, while groups F and D fed with normal feed and supplemented with vitamin E 100 ppm and 1% Moringa oleifera, respectively, whereas groups E and C were fed with 400 ppb aflatoxin containing feed and ameliorated with vitamin E 100 ppm and 1% Moringa oleifera, respectively. This study was continued for 2 months and immunologic disorders and reproductive parameters were observed during the trial. To find out immunological status lymphoproliferative response to phytohemagglutinin-P (PHA-P), antibody titers against sheep red blood cells (SRBCs) and carbon clear assay were performed by collecting samples from five birds from each group. The whole data was measured by ANOVA test, and group means were compared by DMR test by using M-Stat C software. Regarding the reproductive status, spermatogenesis, blood testosterone level, testes weight, testes histology, sperm motility, and morphology were negatively affected by aflatoxins, but these deviations positively ameliorated by vitamin E and Moringa. Vitamin E and Moringa found advantageous in boosting the immune status of affected bird. All the immunological parameters including antibody titers against sheed red blood cells, lymphoproliferative response to avian tuberculin and phagocytic potential of macrophages were suppressed by AFB1 however in control, Moringa and vitamin E groups these immunological responses were significantly higher.
Sujet(s)
Aflatoxines , Moringa oleifera , Animaux , Mâle , Aliment pour animaux/analyse , Poulets , Mobilité des spermatozoïdes , Tocophérols , Vitamine E/pharmacologieRÉSUMÉ
Mycotoxins frequently contaminate a variety of food items, posing significant concerns for both food safety and public health. The adverse consequences linked to poisoning from these substances encompass symptoms such as vomiting, loss of appetite, diarrhea, the potential for cancer development, impairments to the immune system, disruptions in neuroendocrine function, genetic damage, and, in severe cases, fatality. The deoxynivalenol (DON) raises significant concerns for both food safety and human health, particularly due to its potential harm to vital organs in the body. It is one of the most prevalent fungal contaminants found in edible items used by humans and animals globally. The presence of harmful mycotoxins, including DON, in food has caused widespread worry. Altered versions of DON have arisen as possible risks to the environment and well-being, as they exhibit a greater propensity to revert back to the original mycotoxins. This can result in the buildup of mycotoxins in both animals and humans, underscoring the pressing requirement for additional investigation into the adverse consequences of these modified mycotoxins. Furthermore, due to the lack of sufficient safety data, accurately evaluating the risk posed by modified mycotoxins remains challenging. Our review study delves into conjugated forms of DON, exploring its structure, toxicity, control strategies, and a novel animal model for assessing its toxicity. Various toxicities, such as acute, sub-acute, chronic, and cellular, are proposed as potential mechanisms contributing to the toxicity of conjugated forms of DON. Additionally, the study offers an overview of DON's toxicity mechanisms and discusses its widespread presence worldwide. A thorough exploration of the health risk evaluation associated with conjugated form of DON is also provided in this discussion.
Sujet(s)
Mycotoxines , Trichothécènes , Animaux , Humains , Contamination des aliments/analyse , Trichothécènes/toxicité , Mycotoxines/toxicité , Mycotoxines/analyse , AlimentsRÉSUMÉ
Antisense transcription, a prevalent occurrence in mammalian genomes, gives rise to natural antisense transcripts (NATs) as RNA molecules. These NATs serve as agents of diverse transcriptional and post-transcriptional regulatory mechanisms, playing crucial roles in various biological processes vital for cell function and immune response. However, when their normal functions are disrupted, they can contribute to human diseases. This comprehensive review aims to establish the molecular foundation linking NATs to the development of disorders like cancer, neurodegenerative conditions, and cardiovascular ailments. Additionally, we evaluate the potential of oligonucleotide-based therapies targeting NATs, presenting both their advantages and limitations, while also highlighting the latest advancements in this promising realm of clinical investigation.Abbreviations: NATs- Natural antisense transcripts, PRC1- Polycomb Repressive Complex 1, PRC2- Polycomb Repressive Complex 2, ADARs- Adenosine deaminases acting on RNA, BDNF-AS- Brain-derived neurotrophic factor antisense transcript, ASOs- Antisense oligonucleotides, SINEUPs- Inverted SINEB2 sequence-mediated upregulating molecules, PTBP1- Polypyrimidine tract binding protein-1, HNRNPK- heterogeneous nuclear ribonucleoprotein K, MAPT-AS1- microtubule-associated protein tau antisense 1, KCNQ1OT- (KCNQ1 opposite strand/antisense transcript 1, ERK- extracellular signal-regulated kinase 1, USP14- ubiquitin-specific protease 14, EGF- Epidermal growth factor, LSD1- Lysine Specific Demethylase 1, ANRIL- Antisense Noncoding RNA in the INK4 Locus, BWS- Beckwith-Wiedemann syndrome, VEGFA- Vascular Endothelial Growth component A.
Sujet(s)
Maladies neurodégénératives , Transcription génétique , Animaux , Humains , Régulation de l'expression des gènes , ARN antisens/génétique , Noyau de la cellule , Mammifères/génétique , Ribonucléoprotéines nucléaires hétérogènes/génétique , Protéine PTB/génétique , Ubiquitin thiolesterase/génétiqueRÉSUMÉ
Atrazine, a herbicide, is used for eradication of broad-leaved herbs in corn crop; and ochratoxins, particularly ochratoxin A (OTA), are major pollutants of poultry diet. Existence of both of these hazardous chemicals as residues is obvious as elucidated by various epidemiological findings. The present study was designed to investigate toxicopathological, serum biochemical and immunological alterations incurred by atrazine alone and/or, in combination with OTA in broilers. For this purpose, one-day old broiler chicks (n = 180) were purchased from a local hatching unit and were fed two levels of atrazine (50 and 150 mg/kg) and one level of OTA (100 µg/kg) in different combinations. Results of this experiment showed a significant reduction in feed intake, body weight gain, relative organ weights, serum total protein, albumin and globulin while there was a significant increase in urea and creatinine levels, decreased antibody response to sheep red blood cells, reduced lymphoproliferative response and phagocytic capacity in groups given OTA and atrazine individually in feed and these effects became more pronounced when atrazine was given in combination with OTA suggesting synergistic effects of both toxicants for each other.
Sujet(s)
Atrazine , Ochratoxines , Animaux , Ovis , Ochratoxines/toxicité , Poulets , Atrazine/toxicité , Aliment pour animaux/analyseRÉSUMÉ
The goal of the research was to find alternative protein sources for animal farming that are efficient and cost-effective. The researchers focused on distillers dried grains with solubles (DDGS), a co-product of bioethanol production that is rich in protein but limited in its use as a feed ingredient due to its high non-starch polysaccharides (NSPs) content, particularly for monogastric animals. The analysis of the Paenibacillus pabuli E1 genome revealed the presence of 372 genes related to Carbohydrate-Active enzymes (CAZymes), with 98 of them associated with NSPs degrading enzymes that target cellulose, hemicellulose, and pectin. Additionally, although lignin is not an NSP, two lignin-degrading enzymes were also examined because the presence of lignin alongside NSPs can hinder the catalytic effect of enzymes on NSPs. To confirm the catalytic ability of the degrading enzymes, an in vitro enzyme activity assay was conducted. The results demonstrated that the endoglucanase activity reached 5.37 U/mL, while beta-glucosidase activity was 4.60 U/mL. The filter paper experiments did not detect any reducing sugars. The xylanase and beta-xylosidase activities were measured at 11.05 and 4.16 U/mL, respectively. Furthermore, the pectate lyase and pectin lyase activities were found to be 8.19 and 2.43 U/mL, respectively. The activities of laccase and MnP were determined as 1.87 and 4.30 U/mL, respectively. The researchers also investigated the effect of P. pabuli E1 on the degradation of NSPs through the solid-state fermentation of DDGS. After 240 h of fermentation, the results showed degradation rates of 11.86% for hemicellulose, 11.53% for cellulose, and 8.78% for lignin. Moreover, the crude protein (CP) content of DDGS increased from 26.59% to 30.59%. In conclusion, this study demonstrated that P. pabuli E1 possesses various potential NSPs degrading enzymes that can effectively eliminate NSPs in feed. This process improves the quality and availability of the feed, which is important for animal farming as it seeks alternative protein sources to replace traditional nutrients.
RÉSUMÉ
Polian vesicle is thought to produce coelomocytes and contribute to the sea cucumber's immune system. Our previous work has indicated that polian vesicle was responsible for cell proliferation at 72 h post pathogenic challenge. However, the transcription factors related to the activation of effector factors and the molecular process behind this remained unknown. In this study, to reveal the early functions of polian vesicle in response to the microbe, a comparative transcriptome sequencing of polian vesicle in V. splendidus-challenged Apostichopus japonicus, including normal group (PV 0 h), pathogen challenging for 6 h (PV 6 h) and 12 h (PV 12 h) was performed. Compared PV 0 h to PV 6 h, PV 0 h to PV 12 h, and PV 6 h to PV 12 h, we found 69, 211, and 175 differentially expressed genes (DEGs), respectively. KEGG enrichment analysis revealed the DEGs, including several transcription factors such as fos, FOS-FOX, ATF2, egr1, KLF2, and Notch3 between PV 6 h and PV 12 h were consistently enriched in MAPK, Apelin and Notch3 signaling pathways related to cell proliferation compared with that in PV 0 h. Important DEGs involved in cell growth were chosen, and their expression patterns were almost the same as the transcriptome profile analysis by qPCR. Protein interaction network analysis indicated that two DEGs of fos and egr1 were probably significant as key candidate genes controlling cell proliferation and differentiation in polian vesicle after pathogenic infection in A. japonicus. Overall, our analysis demonstrates that polian vesicles may play an essential role in regulating proliferation via transcription factors-mediated signaling pathway in A. japonicus and provide new insights into hematopoietic modulation of polian vesicles in response to pathogen infection.
Sujet(s)
Stichopus , Animaux , Stichopus/génétique , Facteurs de transcription/génétique , Analyse de profil d'expression de gènes , Transcriptome , Prolifération cellulaire , Immunité innéeRÉSUMÉ
Deoxynivalenol (DON) is one of the most harmful and well-known toxins present in food and animal feed throughout the world. Citrobacter freundii (C. freundii-ON077584), a novel DON-degrading strain, was isolated from rice root-linked soil samples. The degrading properties, including DON concentrations, incubation pH, incubation temperatures, bacterial concentrations, and acid treatment effect on degradation, were evaluated. At pH 7 and an incubation temperature of 37 °C, C. freundii demonstrated the capability to degrade more than 90% of DON. The degraded products of DON were identified as 3-keto-DON and DOM-1, which were confirmed by High Performance Liquid Chromatography (HPLC) and Ultra-Performance Liquid Chromatography hyphenated with Tandem Mass Spectrometry (UPLC-MS/MS) analyses. The mechanism of DON degradation into 3-keto-DON and DOM-1 by this bacterial strain will be further explored to identify and purify novel degrading enzymes that can be cloned to the microorganism and added to the animal feed to degrade the DON in the digestion tract.
Sujet(s)
Mycotoxines , Animaux , Mycotoxines/analyse , Chromatographie en phase liquide , Citrobacter freundii/métabolisme , Spectrométrie de masse en tandem , Bactéries/métabolisme , Contamination des aliments/prévention et contrôle , Contamination des aliments/analyseRÉSUMÉ
Zearalenone (ZEN) contamination of various foods and feeds is an important global problem. In some animals and humans, ZEN causes significant health issues in addition to massive economic losses, annually. Therefore, removal or degradation of the ZEN in foods and feeds is required to be done. The conventional physical and chemical methods have some serious issues including poor efficiency, decrease in nutritional value, palatability of feed, and use of costly equipment. Research examined microbes from diverse media for their ability to degrade zearalenone and other toxins, and the findings of several investigations revealed that enzymes produced from microbes play a significant role in the degradation of mycotoxins. In established bacterial hosts, genetically engineered technique was used to enhance heterologously produced degrading enzymes. Then, the bio-degradation of ZEN by the use of micro-organisms or their enzymes is much more advantageous and is close to nature and ecofriendly. Furthermore, an effort is made to put forward the work done by different scientists on the biodegradation of ZEN by the use of fungi, yeast, bacteria, and/or their enzymes to degrade the ZEN to non-toxic products. KEY POINTS: â¢Evolved microbial strains degraded ZEA more quickly â¢Different degrading properties were studied.
Sujet(s)
Mycotoxines , Zéaralénone , Animaux , Aliments , Contamination des aliments , Mycotoxines/métabolisme , Saccharomyces cerevisiae/métabolisme , Zéaralénone/métabolismeRÉSUMÉ
Aflatoxin B1 (AFB1) contamination in feed and food seriously threatens the healthy growth of animals and humans, and it may lead to huge economic losses in livestock and poultry production. Therefore, screening of high-efficient AFB1-degrading bacteria is necessary to ensure the safety of feed and food. The study aims to isolate and characterize bacteria from various sources to explore its AFB1 degradation potential. Fifteen bacterial were obtained using a medium containing coumarin as the sole carbon source; only one strain showed a good-degrading ability in culture media by adding AFB1 and it was selected for further studies. A gram-negative and spore-forming, designated E1, was identified as Paenibacillus pabuli, with the highest sequence similarity to P. pabuli NBRC13638T (98.97%). The growth of the strain E1 was observed under 22-47 °C, pH 5.5-9.5 and NaCl concentration 0-6% (w/v), with optimum growth at 37 °C, pH 7.5 and 1% NaCl. The biodegradation characteristics of object strain were detected by high performance liquid chromatography (HPLC). The degradation ratio of AFB1 reached 55% at 24 h and 70.2% at 48 h. After 96 h, the degradation rate of AFB1 reached 85.9%. The active degradation components were present in the cell-free supernatant of strain E1, and the degradation ratio of AFB1 reached 80.0% after 96 h. It is the first report that genus Paenibacillus could degrade AFB1. Moreover, E1 has highly adaptable to diverse environmental conditions. It will be a potential candidate for biodegradation of mycotoxins in feed and food.
Sujet(s)
Aflatoxine B1 , Paenibacillus , Animaux , Dépollution biologique de l'environnement , Milieux de culture , Humains , Paenibacillus/génétiqueRÉSUMÉ
The emergence and rapid spread of multidrug-resistant bacteria has induced intense research for novel therapeutic approaches. In this study, the Acinetobacter baumannii bacteriophage D2 (vB_AbaP_D2) was isolated, characterized and sequenced. The endolysin of bacteriophage D2, namely Abtn-4, contains an amphipathic helix and was found to have activity against multidrug-resistant Gram-negative strains. By more than 3 log units, A. baumannii were killed by Abtn-4 (5 µM) in 2 h. In absence of outer membrane permeabilizers, Abtn-4 exhibited broad antimicrobial activity against several Gram-positive and Gram-negative bacteria, such as Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Enterococcus and Salmonella. Furthermore, Abtn-4 had the ability to reduce biofilm formation. Interestingly, Abtn-4 showed antimicrobial activity against phage-resistant bacterial mutants. Based on these results, endolysin Abtn-4 may be a promising candidate therapeutic agent for multidrug-resistant bacterial infections.
Sujet(s)
Acinetobacter baumannii , Anti-infectieux , Bactériophages , Antibactériens/pharmacologie , Endopeptidases , Bactéries à Gram négatif , Bactéries à Gram positif , Tests de sensibilité microbienneRÉSUMÉ
Edwardsiellosis, an extremely harmful disease can be caused by Edwardsiella tarda, severely restricts the development of turbot (Scophthalmus maximus) farming worldwide, especially in China. This study aimed to establish an effective and feasible prophylaxis by feeding chitosan-alginate coated egg yolk immunoglobulin (IgY) against E. tarda 2CDM001 infections in the process of turbot farming. Enzyme-linked immunosorbent assays proved that the obtained specific IgY could specifically target E. tarda 2CDM001 and five other E. tarda isolates (1a5p, Hz-s, 1a1s, fs-a1 and 58p8). In-vitro, the bacteriostatic effects of specific IgY showed dose dependencies at concentrations ranging from 1 to 10 mg/mL. Moreover, E. tarda 2CDM001 incubated with 10 mg/mL specific IgY could induce the destruction of cell wall structures and significantly decrease the bacterial surface hydrophobicity (p < 0.05). In this study, turbots were challenged with 107 CFU E. tarda 2CDM001 after seven days of continuous feeding with basal diets containing microencapsulated IgYs. Survival rates of the 5%, 3% and 1% microencapsulated specific IgY groups were 63.3%, 56.7% and 20% on the tenth day post infection, respectively, while the turbots in the positive control and non-specific IgY groups all died within ten days. Oral administration of basal diets containing 5% microencapsulated specific IgY significantly reduced IL-1ß, IL-8, TNF-α and C3 transcript levels in the head kidney and spleen of turbots compared with the positive and non-specific IgY groups at 24 h after E. tarda 2CDM001 challenging (p < 0.05). Pathological increase of leukocytes in the specific IgY group was significantly lower than that in the positive control and non-specific IgY groups (p < 0.05), decreasing slowly after 24 h of infection and showing a recovery trend. Erythrocyte counts and hemoglobin concentrations of turbots in positive and non-specific IgY groups showed a marked decrease compared with the negative and specific groups at 96 h after E. tarda 2CDM001 infection (p < 0.05). These results suggest that passive immunity via feeding microencapsulated specific IgY could be used as a valuable preventative in turbot against E. tarda 2CDM001 infections.
Sujet(s)
Edwardsiella tarda/immunologie , Jaune d'Åuf/immunologie , Infections à Enterobacteriaceae/prévention et contrôle , Maladies des poissons/prévention et contrôle , Poissons plats/immunologie , Immunoglobulines/administration et posologie , Administration par voie orale , Alginates/administration et posologie , Animaux , Anticorps antibactériens/sang , Poulets , Chitosane/administration et posologie , Cytokines/génétique , Préparation de médicament , Infections à Enterobacteriaceae/mortalité , Infections à Enterobacteriaceae/médecine vétérinaire , Femelle , Maladies des poissons/mortalité , Poissons plats/sang , Poissons plats/génétique , Immunisation , Immunoglobulines/sangRÉSUMÉ
This work describes the characterization and genome annotation of a new lytic phage, vB_EtaM_ET-ABTNL-9 (referred to as PETp9), isolated from waste water samples collected in Dalian, China, that can kill bacteria of the species Edwardsiella tarda. The genome of phage PETp9 is a circular double-stranded DNA molecule that is 89,762 bp in length with a G+C content of 37.26%, contains 132 ORFs, and encodes one tRNA. Phylogenetic analysis indicated that phage PETp9 should be considered a novel phage.
Sujet(s)
Bactériophages/classification , Bactériophages/isolement et purification , Edwardsiella tarda/virologie , Génome viral , Analyse de séquence d'ADN , Eaux usées/virologie , Bactériolyse , Bactériophages/génétique , Bactériophages/croissance et développement , Composition en bases nucléiques , Chine , ADN circulaire/génétique , ADN viral/génétique , Annotation de séquence moléculaire , Phylogenèse , Similitude de séquencesRÉSUMÉ
BACKGROUND: The objective of the study is to observe frequency of various clinical manifestations of trachoma in rural population. This observational study was conducted at Khalifa Gul Nawaz Teaching Hospital (KGNTH), Bannu, Pakistan from April 2016 to Jan 2017. METHODS: Patients visiting for ocular complaints underwent initial screening that included demographic details and documentation of unaided as well as best corrected visual acuity (BCVA) which was followed by detailed slit lamp examination of anterior segment including eversion of upper lid for assessment of changes in upper tarsal conjunctivas by consultant ophthalmologist. A total of 648 patients who had clinical presentation of trachoma were included in the study. Patients who had other forms of conjunctivitis, trichiasis, entropion, corneal opacification and vascularization due to causes other than trachoma were excluded. Patients were categorized according to age in three groups (Group 1-3) and according to stages of trachoma in five groups (TF, TI, TS, TT and TO). RESULTS: Six hundred and forty-eight (648) were examined in this cross-sectional survey with a mean age of 14.3+14.2 years. Mean unaided visual acuity and BCVA of the patients was 0.12+.24 and 0.07+0.18 respectively. Groups-1 comprised of 86.7% of the patients and stage TF of trachoma was the most prevalent stage accounting for 70.06% of the patients. CONCLUSIONS: Trachoma is a serious community health problem with various clinical manifestations in different age groups. Awareness and educational programs are required to be conducted in schools and vocational training centres regarding its mode of transmission and control..
Sujet(s)
Conjonctivite/microbiologie , Entropion/microbiologie , Population rurale , Trachome/complications , Trachome/épidémiologie , Trichiasis/microbiologie , Adolescent , Adulte , Sujet âgé , Enfant , Enfant d'âge préscolaire , Études transversales , Femelle , Humains , Mâle , Adulte d'âge moyen , Pakistan/épidémiologie , Prévalence , Acuité visuelle , Jeune adulteRÉSUMÉ
OBJECTIVE: To assess the mean change in interpalpebral fissure height and marginal reflex distance after brow suspension with autogenous fascia lata sling in patients of ptosis. METHODS: This was a Quasi experimental study conducted at Department of Ophthalmology, Mayo Hospital, King Edwards Medical University Lahore, from Jan 2013 to June 2016. Included were the patients who had unilateral or bilateral ptosis with poor levator function (< 5 mm). Informed consent was obtained from all patients after explaining about the research project. Patients were admitted in ward and all of them underwent surgery by a single surgical team. The surgical procedure was performed in supine position under general anesthesia in children and uncooperative patients. Patients were followed at week 4, 8, 12 and 24 to observe vertical interpalpebral fissure height and marginal reflex distance. RESULTS: The mean age of the patients was 9.03 ± 5.26 years. The mean Inter palpebral fissure height (IPFH) was 4.40±0.91 mm and mean MRD was 0.50 ± 1.00 mm before surgery while after surgery it was 7.41±0.76 mm and 3.10 ± 1.50 mm respectively at 04 weeks. The mean IPFH and MRD at 24 weeks postoperatively were 8.43±0.98 mm and 3.60 + 1.50 mm respectively. The mean change in IPFH and MRD at 24th week, were 3.90 ± 0.34 mm and 3.50 ± 1.00 mm. CONCLUSION: Brow suspension with fascia lata sling is safe and effective technique for correction of ptosis with poor levator function.