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Synthetic antimicrobials have a negative impact on food quality and consumer health, which is why natural antimicrobials are urgently needed. Coagulase-negative staphylococci (CoNS) has gained considerable importance for food poisoning and infection in humans and animals, particularly in biofilms. As a result, this study was conducted to control the CoNS isolated from food samples in Egypt. CoNS isolates were selected on the basis of their antibiotic susceptibility profiles and their biofilm-associated behavior. In this context, a total of 29 different bacteriophages were isolated and, in particular, lytic phages (6 isolates) were selected. The host range and physiological parameters of the lytic phages have been studied. Electron microscopy images showed that lytic phages were members of the families Myoviridae (CoNShP-1, CoNShP-3, and CoNSeP-2 isolates) and Siphoviridae (CoNShP-2, CoNSsP-1, and CoNSeP-1 isolates). CoNShP-1, CoNShP-2, and CoNShP-3 were found to be virulent to Staphylococcus haemolyticus, CoNSsP-1 to Staphylococcus saprophyticus and CoNSeP-1 and CoNSeP-2 to Staphylococcus epidermidis. Interestingly, the CoNShP-3 exhibited a typical polyvalent behavior, where not only lysis CoNS, but also other genera include Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA), Bacillus cereus and Bacillus subtilis. In addition, CoNShP-3 phage showed high stability at different temperatures and pH levels. Indeed, CoNShP-3 phage showed an antibiofilm effect against Staphylococcus epidermidis CFS79 and Staphylococcus haemolyticus CFS43, respectively, while Staphylococcus saprophyticus CFS28 biofilm was completely removed. Finally, CoNShP-3 phage demonstrated a high preservative efficacy over short and long periods of storage against inoculated CoNS in chicken breast sections. In conclusion, this study highlights the control of CoNS pathogens using a polyvalent lytic phage as a natural antibacterial and antibiofilm agent from a food safety perspective.

BackgroundAltered regulation of the complement system is associated with multiple kidney diseases. CD35, CD55 and CD59 regulate the complement system, and changes in their expression have previously been linked with kidney disease. This study assessed whether changes in the expression levels of these proteins are associated specifically with chronic kidney disease (CKD) to understand its pathogenesis.Materials and methodsSixty CKD patients and 60 age-matched controls were enrolled and divided into two groups: Group I (n=30 pediatric patients and n=30 controls) and Group II (n=30 adult patients and n=30 controls). The expression of CD35, CD55 and CD59 on peripheral blood cells was evaluated by flow cytometry as the proportion of positive cells expressing the marker and mean fluorescence intensity (MFI), also the relation of these markers to the stage of CKD was also evaluated.ResultsPediatric and adult CKD patients had significantly lower proportion of erythrocytes expressing CD35, CD55 and CD59 than healthy controls (P<0.001). In pediatric CKD patients, there was no significant difference in the three studied markers on neutrophils, lymphocytes and monocytes. The changes in expression of CD35, CD55 and CD59 on leukocytes were more pronounced in adult patients, who had lower proportion of CD59-positive neutrophils, CD35- and CD59-positive lymphocytes, and CD59-positive monocytes, as well as lower expression of CD59 on neutrophils and monocytes than adult controls (P<0.001, P=0.019, P<0.001, P=0.026, P<0.001 and P=0.003, respectively). The eGFR directly correlated with the proportion of positivity of some of those markers on peripheral leukocytes while there was inverse correlation between the disease stage and the same markers.ConclusionThere are alterations in the patterns of expression of complement regulatory proteins CD35, CD55 and CD59 on peripheral blood cells of patients with CKD compared with healthy controls.

AIM:To assess the long-term effectiveness of hepatitis B virus vaccine and the need for a booster dose among children who received three doses of vaccine during infancy in Red Sea Governorate.METHODS:A cross-sectional study was performed. Interviews with children (9 months to 16 years) and parents were done. Blood samples to assess Hepatitis B markers were tested. Children showing no seroprotection received a booster dose to assess their anamnestic response after four weeks and one year later.RESULTS:None of the participants had evidence of chronic Hepatitis B. The seroprotection rate was 23.3% and it significantly decreased with age. Multivariate logistic analysis revealed that older age was the significant predicting variable for having no seroprotective level, while baseline anti-HBs level < 3.3 IU/L was the predicting variable for not developing early anamnestic response or loss of late anamnestic response.CONCLUSION:Long-term immunity persists among children who received complete series of hepatitis B vaccination during infancy even in absence or reduction of anti-HBs over time. Therefore, a booster dose is not necessary to maintain immunity till the age of sixteen.

Background Mature bone marrow T lymphocytes and NK may have a special relevance in the control of the malignant growth. Objective We aimed to assess the percentage of the residual BM T-cells, (T-helper –T-cytotoxic- NKT) and the NK cells of childhood precursor B-lymphoblastic leukemia (B-ALL) as an indicator of innate and adaptive immunity in these patients. Subjects and Methods This study was conducted on 40 B-ALL patients, and 40 apparently healthy matched children served as a control group. The flow cytometry was used to assess the percentage of the residual BM T-cells (T-helper, T-cytotoxic and NKT), and the NK cells. Results Compared with the control group, the percentage of the residual BM T-cells, its subtypes (T-helper, T-cytotoxic), and NKT cells in addition to the NK cells was significantly decreased in Group IA, and Group IB, but there was no significant difference between Group IA and Group IB in all studied parameters. In terms of the CD4/CD8 ratio, there was a significant increase in Group IA as compared to the control group (P < 0.026), but there were no significant statistical differences in CD4/CD8 ratio between Groups IB, and the control. Likewise, in CD4/CD8 ratio between groups IA, and Groups IB (P > 0.05). The percentage of NK, and NKT cells shows a significant increase in Hepatomegaly and Splenomegaly, as compared to non-Hepatomegaly and non-Splenomegaly patients of Groups IB (P < 0.05). However, there was a significant increase in statistical differences in the percentage of NKT cell between non-Splenomegaly, as compared to Splenomegaly patients of Group IA (P < 0.05). Additionally, there is a negative correlation between B.M Blast% to CD4/CD8 ratio and NK%, but there is no significant correlation between B.M Blast% to NK T% in the group 1 A.