Antiviral activity of chitosan nanoparticles for controlling plant-infecting viruses

Chitosan nanoparticles (ChiNPs) are a potentially effective means for controlling numerous plant diseases. This study firstly describes the antiviral capabilities of ChiNPs to control plant viral diseases compared to its bulk form. Bean yellow mosaic virus (BYMV) was used as a model plant virus affecting faba bean plants and many other legumes. The antiviral effectiveness of ChiNPs and chitosan were evaluated as a curative application method, using six dosage rates (50, 100, 200, 250, 300 and 400 mg/L). Results indicated that ChiNPs curatively applied 48 h post virus inoculation entirely inhibit the disease infectivity and viral accumulation content at 300 mg/L and 400 mg/L. The virus titre was greatly alleviated within the plant tissues by 7.71% up to100% depending on ChiNP dosage rates. However, chitosan used in its bulk-based material form revealed a relatively low to an intermediate reduction in virus infectivity by 6.67% up to 48.86%. Interestingly, ChiNPs affect the virus particle’s integrity by producing defective and incomplete BYMV viral particles, defeating their replication and accumulation content within the plant tissues. Simultaneously, ChiNP applications were appreciably shown to promote the pathogenesis-related (PR-1) gene and other defence-related factors. The mRNA of the PR-1 gene was markedly accumulated in treated plants, reaching its maximum at 400 mg/L with 16.22-fold relative expression change over the untreated control. Further, the total phenol dynamic curve was remarkably promoted for 30 days in response to ChiNP application, as compared to the untreated control. Our results provide the first report that chitosan-based nanomaterials have a superior effect in controlling plant viruses as an antiviral curing agent, suggesting that they may feasibly be involved in viral disease management strategies under field conditions without serious health concerns and environmental costs. Significance: • Our findings show that chitosan nanoparticles have a powerful curing antiviral activity against BYMV disease. These findings open the door for the use of eco-friendly nano-based tools in controlling numerous plant viruses. The use of eco-friendly nano-based materials could result in a successful integrative control strategy for plant viruses under field conditions, negating the need for the conventional measure used to control most of the insect-transmitted plant viruses, that is insecticide application against vector insects

Bacterial Diseases Affecting the Cultured Sepia Officinalis Leading to Increase Mortality Rates in The Laboratory

The early growth, mortality rates and bacterial infections of the cultured Sepia Officinalis were experimentally studied in the laboratory. Two hundred eighty-five sepia larvae were hatched and placed in a 100-liter capacity rectangular glass aquarium (filled with seawater) in the laboratory. The Sepia individuals (285 individuals) were divided into two groups the first fed on a mixture of amphipods, rotifers and artemia and the second group fed only on amphipods to follow their growth and mortality. The second group was observed to grow faster with length 6.76 ± 0.06mm and weight 0.11 ± 0.01gm than the first one. The survival rate was 100% by the end of the first week and decreased gradually by the end of the second week. The recorded mortality rate reached 49% by the day 15th, where they infected with bacterial disease of Vibrio alginolyticus. The clinical signs of the diseased S. Officinalis were lethargic condition, food fasting and multiple skin ulcers with white-gray discoloration were observed and appeared on the body. The main postmortem lesions were congestion of the internal organ, beside the presence of ascetic fluid. The mortality among the diseased Sepia was increased by age; however, it may cause death of most individuals by increasing time more than two weeks. The findings of antibiotic sensitivity test cleared that the isolated V. alginolyticus was sensitive to amoxiclav (amoxicillin-clavulanate), streptomycin, ciprofloxacin and chloramphenicol. Controversially, it was resistant to oxytetracycline, tobramycin, gentamycin and enrofloxacin

Bacterial Diseases Affecting the Cultured Sepia Officinalis Leading to Increase Mortality Rates in The Laboratory

The early growth, mortality rates and bacterial infections of the cultured Sepia Officinalis were experimentally studied in the laboratory. Two hundred eighty five sepia larvae were hatched and placed in a 100 liter capacity rectangular glass aquarium (filled with seawater) in the laboratory. The Sepia individuals (285 individuals) were divided into two groups the first fed on a mixture of amphipods, rotifers and artemia and the second group fed only on amphipods to follow their growth and mortality. The second group was observed to grow faster with length 6.76 ± 0.06mm and weight 0.11 ± 0.01gm than the first one. The survival rate was 100% by the end of the first week and decreased gradually by the end of thesecond week. The recorded mortality rate reached 49% by the day 15th, where they infected with bacterial disease of Vibrio alginolyticus. The clinical signs of the diseased S. Officinalis were lethargic condition, food fasting and multiple skin ulcers with white-gray discoloration were observed and appeared on the body. The main post mortem lesions were congestion of the internal organ, beside the presence of ascetic fluid. The mortality among the diseased Sepia was increased by age; however it may causes death of most individuals by increasing time more than two weeks. The findings of antibiotic sensitivity test cleared that the isolated V. alginolyticus was sensitive to amoxiclav (amoxicillin-clavulanate), streptomycin, ciprofloxacin and chlormphinicol. Controversially, it was resistant to oxytetracycline, tobramycin, gentamycine and enrofloxacin.Keywords: Sepia Officinalis - growth rate - mortality rate - bacterial infection

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

WSES guidelines for management of Clostridium difficile infection in surgical patients

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.Peer reviewe

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Antiviral activity of chitosan nanoparticles for controlling plant-infecting viruses

Chitosan nanoparticles (ChiNPs) are a potentially effective means for controlling numerous plant diseases. This study firstly describes the antiviral capabilities of ChiNPs to control plant viral diseases compared to its bulk form. Bean yellow mosaic virus (BYMV) was used as a model plant virus affecting faba bean plants and many other legumes. The antiviral effectiveness of ChiNPs and chitosan were evaluated as a curative application method, using six dosage rates (50, 100, 200, 250, 300 and 400 mg/L). Results indicated that ChiNPs curatively applied 48 h post virus inoculation entirely inhibit the disease infectivity and viral accumulation content at 300 mg/L and 400 mg/L. The virus titre was greatly alleviated within the plant tissues by 7.71% up to100% depending on ChiNP dosage rates. However, chitosan used in its bulk-based material form revealed a relatively low to an intermediate reduction in virus infectivity by 6.67% up to 48.86%. Interestingly, ChiNPs affect the virus particle’s integrity by producing defective and incomplete BYMV viral particles, defeating their replication and accumulation content within the plant tissues. Simultaneously, ChiNP applications were appreciably shown to promote the pathogenesis-related (PR-1) gene and other defence-related factors. The mRNA of the PR-1 gene was markedly accumulated in treated plants, reaching its maximum at 400 mg/L with 16.22-fold relative expression change over the untreated control. Further, the total phenol dynamic curve was remarkably promoted for 30 days in response to ChiNP application, as compared to the untreated control. Our results provide the first report that chitosan-based nanomaterials have a superior effect in controlling plant viruses as an antiviral curing agent, suggesting that they may feasibly be involved in viral disease management strategies under field conditions without serious health concerns and environmental costs.Significance: Our findings show that chitosan nanoparticles have a powerful curing antiviral activity against BYMV disease. These findings open the door for the use of eco-friendly nano-based tools in controlling numerous plant viruses. The use of eco-friendly nano-based materials could result in a successful integrative control strategy for plant viruses under field conditions, negating the need for the conventional measure used to control most of the insect-transmitted plant viruses, that is insecticide application against vector insects

Diversity of

Seasonal abundance, biomass, and taxonomic composition of copepods in El-Mex Bay (Southeastern Mediterranean region) were studied from autumn 2011 to 2012. Most species within the copepod communities displayed a clear pattern of succession throughout the investigation period. Generally copepods were the predominant group. They contributed numerically 57% of the total zooplankton counts with an average of 5083 organisms/m3 and a total number of 203,333 individuals. The bay harbored 50 species belonging to 28 genera within 19 families and 4 orders under one class. Calanoids were represented by 24 species which formed 31.6% of total copepods predominantly Acartia clausi, Calocalanus pavo, Clausocalanus furcatus, Eucalanus crassus, Nannocalanus minor, Paracalanus parvus, Eucalanus subcrassus, and Temora longicornis. Cyclopoids comprised 13 species of which Acanthocyclops americanus, Halicyclops magniceps, Oithona attenuata, and Oithona nana were the most abundant adult copepods. Eleven Harpacticoid species were also recorded with Euterpina acutifrons, Microsetella norvegica, Onychocamptus mohammed being the most prevalent. It was found however, that two Poecilostomatoida species were rarely encountered in the plankton Oncaea minuta and Corycaeus typicus. Copepod larvae and copepodite stages formed the main bulk of copepod Fauna as noticed in the El-Mex Bay during the investigation period. Their percentage was 36.7% of the total count and their total numbers were 74,629 individuals with an average of 1866 organisms/m3. The persistent relationships between total copepod counts, copepod orders, and physico-chemical variables suggested that physical factors operate on the copepod communities, either directly to limit maximum distribution along the bay, or indirectly on abundance

Environmental

Rotifers are one of the most common, abundant components of plankton in the coastal waters of the Mediterranean Sea, which means that they can be used as bio-indicators and provide useful information on the long-term dynamics of the El-Mex Bay ecosystem. Rotifera species were quantitatively and qualitatively assessed in the El-Mex Bay, west of Alexandria at eight stations to study spatial, temporal, dominance, and abundance of the rotifer community and their relation with changes in environmental conditions. Samples were collected seasonally from autumn 2011 to autumn 2012. Ecological parameters were determined and correlated with total rotifers abundance to gain information about the forces that structure the rotifer community in this dynamic environment. A total of 38 rotifer species were identified belonging to 16 genera within 12 families and 3 orders under one class and contributed about 12.1% of the total zooplankton in the study area with an average of 1077 specimens/m3. Maximum density was observed in summer 2012 with an average of 1445 specimens/m3. During autumn 2011 rotifers appeared in low density (434 specimens/m3). The predominant species Ascomorpha saltans, Brachionus urceolaris, Synchaeta oblonga, Synchaeta okai, Synchaeta pectinata and Synchaeta tremula were recorded in all study stations of the bay. Salinity, temperature, depth, and chlorophyll-a concentration were the most important environmental factors co-related with the abundance of rotifers in the El-Mex Bay. A significant positive correlation between the total rotifer abundance and chlorophyll-a was observed during winter 2012 and summer 2012 (r = 0.763 and r = 0.694, respectively, at p ⩽ 0.05)